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GuardBreaker: Derailing AI-assisted malware analysis with a code comment

ESET names 'GuardBreaker': UAC-0099 embeds a nuclear-weapon question in VBScript comments to trip LLM scanner guardrails during analysis of its MATCHBOIL loader.

ESET researchers observed the Russia-aligned group UAC-0099 inserting a decoy prompt injection into a VBScript used to install its MATCHBOIL loader in an attack against a Ukrainian target, aiming to make LLM-based code scanners refuse and stop inspecting the file. The comment triggers safety guardrails with a request about building a nuclear weapons but has no runtime effect. Similar LLM-thwarting tricks have appeared in malicious PyPI and npm packages reported by Socket and StepSecurity. ESET recommends multi-model cross-validation of AI-assisted analysis and treating missing LLM output as requiring further checks.

ESET WeLiveSecurityupdated · 4d agofirst · 6d agoAI safety & security 3 sources1

Critical Issabel PBX Command Execution Vulnerability Exploited in the Wild

Unauthenticated attackers exploit CVE-2026-89026 in Issabel PBX via forged JWT tokens to run OS commands; exploitation observed since September 9.

CVE-2026-89026 (CVSS v4 9.3) stems from a hard-coded HS256 JWT signing key in Issabel Framework's pbxapi/index.php, letting unauthenticated attackers forge bearer tokens and execute OS commands through the Asterisk Manager Interface originate endpoint. Issabel Framework versions before commit b97dbaf0b71c1c36f841e672b664afbeb02773bd are affected. Shadowserver Foundation first observed exploitation on September 9, 2026, and VulnCheck added the flaw to its Known Exploited Vulnerabilities database.

Cyber Security News · 1h agoExploit / PoC in the wildCVE-2026-89026

Attackers conceal phishing lures using invisible Unicode characters

Threat actors use invisible Unicode characters (ASCII smuggling) to hide phishing lures and evade email security filters.

Threat actors have adopted the ASCII smuggling technique in phishing campaigns, embedding invisible Unicode characters in emails to conceal malicious lures. The approach is designed to evade email security filters that scan for visible phishing indicators. The report gives no victim counts or named campaigns.

BleepingComputer · 10d agoPhishing & fraud in the wild

I Think the Military Commissary Freezers Were Hacked

Refrigeration failures at six-plus US military commissaries prompt speculation of a cyber attack on DeCA's remote monitoring systems; Pentagon acknowledges possible disruption.

The author documents near-simultaneous freezer and refrigeration failures at confirmed installations including Fort Huachuca, F.E. Warren AFB, Fort Irwin and Travis AFB on August 26-27, with freezers entering defrost mode that heated and spoiled food. DeCA's Remote Monitoring Control System controls defrost across roughly 182 locations, and an unverified comment attributed the Fort Huachuca failure to a network issue. Stars and Stripes and Military Times independently reported the multi-base failures, and the Pentagon acknowledged a 'possible refrigeration disruption,' though no evidence of hacking has been confirmed.

Lobsters · security · 13d agoData breach

ASCII smuggling isn't just an AI security risk

Microsoft tracked a phishing campaign peaking at 2.37 million daily messages that hid financial-lure keywords with invisible Unicode tag characters to evade filters.

Microsoft researchers uncovered a large phishing campaign that inserted invisible Unicode tag characters (e.g., U+E0020) inside common financial keywords like 'funding', splitting words so keyword, signature, and regex matches fail. The campaign peaked at more than 2.37 million messages in late February 2026, ran from about 150 finance-themed sender domains on a strict weekday-only schedule, and gradually declined to under 20% of peak weekday volume by late March, with residual spikes through mid-June. The technique repurposes ASCII smuggling, normally used for indirect prompt injection against AI assistants, for traditional email phishing evasion. Microsoft advises defenders to strip or fold invisible Unicode code points before content matching and to watch for bulk weekday spikes from churning finance-themed domains.

The Register · Security · 11d agoPhishing & fraud in the wild1

Exploitation of Sangoma Switchvox flaw is underway (CVE-2026-9586)

Attackers actively exploit SQL injection flaw CVE-2026-9586 in unauthenticated Sangoma Switchvox endpoints, dropping reverse shells and second-stage cryptominer malware.

CVE-2026-9586, an unauthenticated SQL injection in Sangoma Switchvox SMB Edition 8.3, lets crafted HTTP POST requests execute arbitrary SQL against the backend PostgreSQL database. Horizon3 honeypots first saw exploitation on August 30, 2026 from IP 176.65.148.184, and dozens of additional source IPs have since joined with scanning payloads and second-stage malware that appears to be a cryptominer. The flaw was patched in Switchvox 8.4.0.2 on July 14, 2026; roughly 4,000 exposed instances exist, mostly in the United States, and exploitation is likely against most of them.

Help Net Security · 14d agoExploit / PoC in the wildCVE-2026-9586

Operation ASTERIX: Anatomy of a Crypto Fraud Pipeline

Rapid7 exposed infrastructure behind a cryptocurrency fraud pipeline using phishing panels, voice-dialing scripts, fake wallets, and AI coding assistants.

Rapid7 researchers identified an exposed web directory on infrastructure used to support a cryptocurrency fraud operation tracked as Operation ASTERIX. The server contained raw phone-number datasets, account-validation tools, enriched lead records, phishing panels, voice-dialing scripts, fake wallet applications, persistence mechanisms, and Telegram exfiltration code. Recovered prompts, shell history, and project files show the operator relied on AI coding assistants to package Electron applications, obfuscate code, troubleshoot builds, and modify phishing infrastructure.

Rapid7 Blog · Aug 17, 2026Phishing & fraud

Campaign Evolution: Darkleech to Pseudo

Unit 42 traces the pseudo-Darkleech campaign, which compromises websites to inject scripts redirecting visitors to exploit kits delivering ransomware.

Palo Alto Networks Unit 42 analyzed the evolution of the pseudo-Darkleech campaign, which injects malicious script into compromised Apache, IIS and WordPress sites to redirect visitors to exploit kits such as Angler and Neutrino. The original Darkleech Apache module infected thousands of servers starting in 2012 and delivered Blackhole EK until that kit disappeared after Paunch's 2013 arrest. From 2015 onward, pseudo-Darkleech delivered ransomware families like CryptoWall and TeslaCrypt, and by early 2016 its injected scripts added obfuscated numeric blocks with frequently changing separator characters. Unit 42 tracks these patterns to help defenders identify compromised websites.

Palo Alto Unit 42 · Aug 17, 2026Threat actor in the wild

Once popular for attacking AI, ASCII smuggling is embraced by spammers

Spammers adopt ASCII smuggling—invisible Unicode tag characters—to evade email filters, with Microsoft Defender detections spiking to 2.5 million per day.

ASCII smuggling hides text in Unicode tag characters (e.g., U+E0041 for "A") that are invisible to humans but readable by LLMs and text processors. The technique gained attention as a stealthy prompt-injection vector and is now used by spammers to obfuscate keywords from email detectors. Microsoft reported Defender for Office smuggling detections jumped from roughly 21,000 per day to over 1.3 million in early February, reaching 2.5 million within four days, before falling sharply in mid-May.

Ars Technica · Security · 11d agoPhishing & fraud

ASCII smuggling crosses over from AI prompt injection to phishing evasion

Microsoft details high-volume phishing campaign using ASCII smuggling (Unicode tag chars) for filter evasion, peaking at 2.3M messages.

Microsoft researchers observed a high-volume finance-themed phishing campaign using invisible Unicode tag characters (U+E0000–U+E007F), a technique known from AI prompt injection research as ASCII smuggling, to split lure words like 'funding' and evade email filters. Telemetry from Microsoft Defender for Office 365 showed signature hits jump from roughly 21,000 messages on February 8, 2026 to more than 1.3 million on February 9, peaking above 2.3 million on February 11, with elevated weekday activity lasting approximately three months. The discovery emerged from prompt injection protection research, showing AI-era evasion techniques crossing into traditional phishing. Most messages were flagged by layered Defender protections rather than a single Unicode-specific signal.

Microsoft Security Blog · 12d agoPhishing & fraud in the wild

Building a Production Greek-English Speech Recognizer

Engineering report details Sophea, a production Greek-English ASR reaching 4.26% WER on public English sets via ROVER ensemble and data-pipeline calibration.

Across 23 training iterations, two architectures, and nine production gates, no single data composition passed all gates; a three-model ROVER ensemble reached 9 of 9 gates and cut overlapping-speech WER from 53.35% to 37.87%. Calibrating an audio-quality filter against in-domain anchors reduced discarded scored Greek audio from 98.7% to 10.6%, and a pre-registered ablation traced a hallucination defect to one training-data package. The sophea/asr-k1 preview arbiter lists 4.26% average WER on eight public English test sets and 25.88% WER on live Greek noisy traffic; no weights or training data are released.

Hugging Face daily papers · 5d agoAI research

New AI Attack Hides Malicious Instructions in Normal-Looking Text to Evade Safety Filters

Check Point researchers show crafted prose hides policy-violating instructions that bypass all tested LLM gatekeepers, including GPT-4o mini and Llama Guard 3.

A new prompt-crafting technique embeds malicious payloads inside grammatical, natural-looking text without Base64, invisible Unicode, or obvious encodings, defeating lightweight pre-screening gatekeepers. In testing, all four evaluated gatekeeper models—gpt-4o-mini-2024-07-18, gpt-oss-safeguard:20b, claude-3-haiku-20240307, and llama-guard3:8b—classified the crafted wrappers as safe at a 100% bypass rate across 23 obfuscated prompts. GPT-5 Thinking in high-reasoning mode recovered and acted on the hidden instruction in 17 of 18 tests (~94.4%), often spending over a minute and multiple Python executions. Researchers recommend paraphrasing untrusted input, hardening gatekeeper policies, and applying defense-in-depth controls for agentic deployments.

GBHackers · 5d agoAI safety & security 2 sources

Hackers Abuse AutoIt to Inject AsyncRAT Into Microsoft-Signed Windows Process

Attackers use AutoIt and an invoice-themed batch file to inject AsyncRAT into Microsoft-signed charmap.exe for stealthy remote access.

Point Wild Threat Intelligence documented a five-stage campaign starting with 'Right-click to open Invoice Details.bat' that launches hidden PowerShell, drops a renamed AutoIt interpreter and encrypted loader into a random Temp folder, and persists via a Startup-folder batch file. The loader decrypts AsyncRAT only in memory and injects it into the Microsoft-signed charmap.exe (Windows Character Map) process, leaving no payload file on disk. The final payload patches AMSI inside the infected process and includes screen-capture code that prepares images for transfer to a command-and-control server at 158[.]51[.]122[.]136:4944.

Cyber Security News · 2d agoMalware in the wild1

AsyncRAT Malware Abuses AutoIt and PowerShell to Hide Inside Legitimate Windows Process

Point Wild details a five-stage AsyncRAT campaign using AutoIt abuse and process injection to hide a .NET RAT inside Microsoft's signed charmap.exe.

Researchers at Point Wild Threat Intelligence analyzed a campaign starting from a lure batch file ('Right-click to open Invoice Details.bat') that launches hidden PowerShell to reconstruct a Base64/XOR-obfuscated payload. The stage drops a renamed signed AutoIt interpreter and loader script into %LOCALAPPDATA%\Temp and achieves persistence via a batch file in the user's Startup folder (T1547.001). The loader decrypts the payload in memory with single-byte XOR key 0x36 and injects it into SysWOW64\charmap.exe using OpenProcess/VirtualAllocEx/WriteProcessMemory/CreateRemoteThread, with PE-sieve confirming an in-memory implanted PE and patched AMSI modules. The final AsyncRAT payload performs screen capture and data theft, with observed C2 at 158[.]51[.]122[.]136:4944 over raw TCP.

GBHackers · 2d agoMalware3· 1 read

ZDI-26-609: Linux Kernel Net Scheduler Packet Classifier Use-After-Free Local Privilege Escalation Vulnerability

The Linux kernel net scheduler packet classifier has a use-after-free (CVSS 7.8) allowing local attackers to escalate privileges from low-privileged code.

ZDI-26-609 describes a use-after-free vulnerability in the Linux kernel's network scheduler packet classifier, with a CVSS score of 7.8. An attacker must first be able to execute low-privileged code on the target system before escalating privileges. The advisory text does not list an assigned CVE identifier.

ZDI Published Advisories · 23d agoVulnerability

microsoft/VibeVoice-ASR-Streaming-7B — new model trending #27 on Hugging Face

Microsoft released VibeVoice-ASR-Streaming-7B, an open streaming ASR model with speaker attribution, custom hotwords, and support for 10 languages under MIT license.

Microsoft Research released VibeVoice-ASR-Streaming-7B on Hugging Face, a unified streaming speech recognition model that continuously transcribes who said what as speech arrives. The 7B model supports customized hotwords for domain-specific terms and 10 languages including Chinese, English, French, German, Italian, Japanese, Korean, Portuguese, Russian, and Spanish. Code is available at github.com/microsoft/VibeVoice with a live demo, and a technical report is on arXiv (2609.02812). The model is licensed under MIT.

Hugging Face trending models · 13d agoModel release1

Bad Likert Judge: A Novel Multi-Turn Technique to Jailbreak LLMs by Misusing Their Evaluation Capability

Unit 42 details the Bad Likert Judge multi-turn jailbreak that abuses LLMs' evaluation capability, raising attack success rates over 60% across six frontier models.

Palo Alto Networks Unit 42 describes the Bad Likert Judge technique, a multi-turn jailbreak that asks a target LLM to act as a Likert-scale judge scoring the harmfulness of example responses. The highest-rated example in each scale can carry harmful content, bypassing the model's internal guardrails. Testing across six state-of-the-art text-generation LLMs showed an average attack success rate increase of more than 60% versus plain attack prompts, with tested models anonymized. The technique targets edge cases rather than typical use, and the article positions the work as guidance for defenders on potential jailbreak risks.

Palo Alto Unit 42 · Aug 17, 2026AI safety & security

WireGuard-Linux Stack-Based Buffer Overflow in lsiio (Linux IIO Userspace Tool) Due to Unbounded fscanf

The Linux IIO userspace tool lsiio has a stack buffer overflow in find_type_by_name() caused by unbounded fscanf reads of oversized filesystem-backed attribute values.

A stack-based buffer overflow exists in the Linux Industrial I/O (IIO) userspace utility lsiio. In the find_type_by_name() function, the program reads an unbounded string from a filesystem-backed attribute into a fixed-size stack buffer using fscanf("%s", ...). A crafted or oversized attribute value causes a write beyond the bounds of the destination buffer. Despite the title's reference to WireGuard-Linux, the flaw described is in the IIO lsiio utility.

Full Disclosure · 12d agoVulnerability

Re: Vulnerabilities fixed in libxml2-2.15.4

libxml2 2.15.4 patches two flaws including a heap buffer overflow in xmlDictAddQString tracked as CVE-2026-86137 and CVE-2026-86138.

libxml2 releases before 2.15.4 are affected by an integer overflow in xmlDictAddQString in dict.c that leads to a heap-based buffer overflow, tracked as CVE-2026-86137 and CVE-2026-86138. The oss-security post from Debian's Salvatore Bonaccorso flags the fixed release for downstream tracking. No exploitation is mentioned in the disclosure.

IndicTriMix: Developing Language Identification Datasets and Models for Tri-Language Code-Mixing

Researchers release IndicTriMix benchmarks and fine-tuned MuRIL and XLM-RoBERTa models for token-level language identification in tri-language code-mixed text.

The paper formulates token-level language identification in code-mixed text as a sequence labeling task and fine-tunes MuRIL and XLM-RoBERTa transformer models for Indian languages. It evaluates on Hindi, Gujarati, and Bengali configurations with manually annotated test sets and proposes two code-mixed generation approaches using parallel trilingual sentences. A public benchmark, annotated test sets, and fine-tuned models are released for reproducibility.

arXiv cs.AI / cs.LG / cs.CL · 5d agoAI research1

Guildma (Astaroth) malware infection from Brazilian Portuguese email, (Tue, Sep 1st)

Guildma (Astaroth) malware spread via geofenced Brazilian Portuguese phishing emails, using zip archives, shortcuts, and AutoIt loaders.

SANS researchers documented a Guildma (Astaroth) malware infection initiated on 2026-08-31 by a malicious Brazilian Portuguese email offering a DocuSign-themed PDF. The delivery link is geofenced to Brazil and requires Brazilian Portuguese browser and OS language settings, otherwise serving a legitimate installer. The infection chain uses a zip archive containing a Windows shortcut that retrieves a DLL saved as an alternate data stream, which installs a compiled AutoIt package for persistence. Unique SHA-256 indicators and HTTPS traffic to Azure-hosted and .cfd domains were observed, with prior reports noting the campaign's abuse of GitHub.

SANS Internet Storm Center · 14d agoMalware in the wild

CS-Guard: Benchmarking LLM Guardrails for Code Generation Security

CS-Guard benchmark shows LLM code-generation guardrails fail widely, with ~50% jailbreak ASR text-to-code and up to 100% code-to-code.

Researchers introduce CS-Guard, the first systematic benchmark for evaluating LLM guardrails for code generation security, covering text-to-code (1,000 malware-generation prompts, 7 jailbreak attacks, and a novel fictional scenario attack) and code-to-code (331 prompts across infilling, completion, and translation). They evaluate 9 guardrails across seven LLMs, finding average jailbreak attack success rates around 50% for text-to-code and 14.4% to nearly 100% for code-to-code. The fictional scenario attack achieves ASR close to 100% across many guardrails, raising reliability concerns for real-world software development. The benchmark and data are released publicly.

arXiv cs.CR · 7d agoAI safety & security1

Phishing Campaign Sends Millions of Emails Using Invisible Unicode to Evade Filters

Microsoft warns of a high-volume phishing campaign using invisible Unicode characters to split keywords like 'funding' and evade filters, peaking at 2.37 million daily messages.

Microsoft's Security Research team documented a high-volume phishing operation inserting deprecated Unicode Tags characters (U+E0000-U+E007F) inside financial keywords such as 'funding' so literal-string and regex email filters stop matching them. The campaign ran on a weekly cadence with 1-2.37 million weekday messages between February and May 15, 2026, peaking on February 26, 2026. It used hundreds of disposable finance-themed sender domains and relayed mail through ActiveCampaign's click-tracking infrastructure (acemlnd[.]com, activehosted[.]com), lending legitimate platform reputation. Microsoft ties the activity to an AI-assisted SBA loan phishing campaign that Fortra's FIRE team disclosed in September 2025.

The Hacker News · 11d agoPhishing & fraud in the wild

SEMA-GUARD: Semantic and Graph-Based Vulnerability Detection in Assembly Code

SEMA-GUARD uses semantic analysis and graph neural networks to detect vulnerabilities in assembly code, achieving 85.1% accuracy on a Juliet-derived benchmark.

SEMA-GUARD is a framework that detects vulnerabilities in compiled programs when source code is unavailable, targeting malware, firmware, and embedded systems analysis. It enriches control flow graphs with low-level execution semantics including stack manipulations, memory accesses, and data flow. Evaluated on a Juliet Test Suite set compiled to assembly and split into function-level chunks, it achieves 85.1% accuracy and an F1 score of 0.801, outperforming purely statistical or structural approaches.

arXiv cs.CR · 23h agoResearch1

Rare Not Random Using Token Efficiency for Secrets Scanning

Researcher proposes token efficiency (string length divided by BPE token count) as a better post-regex filter than entropy for secrets scanning, validated on CredData.

The post explores whether Byte-Pair Encoding tokenization can replace Shannon entropy as the primary filter for candidate secrets captured by regex in tools like Gitleaks. It defines 'token efficiency' as string length divided by token count under the cl100k_base tokenizer; secret-like strings such as GitHub tokens tokenize into many small tokens and score low, while natural text scores high. Evaluating labeled secrets from the CredData dataset shows a usable separation, with roughly 2.5 suggested as a minimum cutoff versus Gitleaks' 3.5 entropy threshold. The technique is positioned as a post-regex filtering step rather than a standalone detector.

Lobsters · security · 4d agoResearch

Re: Linux kernel LPEs: ZcopyReaper (CVE-2026-43502) and 20 more

oss-security thread discusses newly disclosed Linux kernel local privilege escalations, including ZcopyReaper (CVE-2026-43502) and about 20 more flaws.

An oss-security mailing list thread discusses newly disclosed Linux kernel local privilege escalation (LPE) issues, headlined by ZcopyReaper (CVE-2026-43502) along with roughly 20 more. Discussants ask whether the many reports could be summarized and note that locking kernel module loading after boot has repeatedly proven an effective mitigation. The visible discussion does not state whether any of the flaws are exploited in the wild or give specific patch guidance beyond the individual reports.

oss-security · 7d agoVulnerabilityCVE-2026-43502

Linux kernel LPEs: ZcopyReaper (CVE-2026-43502) and 20 more

Researchers disclosed CVE-2026-43502 (ZcopyReaper), a Linux kernel local privilege escalation in the RDS zerocopy send path, fixed in v7.1-rc3.

Yuan Tan reported a Linux kernel local privilege escalation in the RDS zerocopy send path, tracked as CVE-2026-43502 and dubbed ZcopyReaper, posted to oss-security. The flaw was introduced in Linux v4.17 and fixed by commit 44b550d88b26, first appearing in mainline v7.1-rc3. The researchers demonstrated local privilege escalation on an openSUSE system running kernel 6.4.0-150600.23.100. The post also references 20 additional Linux kernel LPEs, though CVE ids were not provided in the excerpt.

oss-security · 8d agoVulnerabilityCVE-2026-43502

Vulnerabilities fixed in libxml2-2.15.4

libxml2 2.15.4 fixes an out-of-bounds read in xmlregexp's NXT macro plus several integer overflow and parsing flaws.

libxml2 2.15.4 (released September 1, 2026) includes security fixes: an out-of-bounds read in the xmlregexp NXT macro, missing overflow checks in dict.c, uri.c, and valid.c, an integer overflow in xmlIO before the writecallback, and an overflow check in xmlXPtrEvalXPtrPart. The release also propagates parseFlags in xmlXIncludeProcess and xmlXIncludeProcessTree. No CVE identifiers, exploitation, or severity ratings are given in the announcement.

oss-security · 11d agoVulnerability

Re: Linux kernel LPEs: ZcopyReaper (CVE-2026-43502) and 20 more

Linux kernel developers discuss a batch of 21 local privilege escalation CVEs, including ZcopyReaper (CVE-2026-43502) in the RDS networking driver.

An oss-security thread examines newly published Linux kernel local privilege escalation issues tracked in the kernel.org security vulnerabilities git repository. CVE-2026-43502, dubbed ZcopyReaper, affects the net/rds (Reliable Datagram Sockets) subsystem. The discussion references roughly 20 additional kernel LPE CVEs published in the 2026 Q3 window.

oss-security · 7d agoVulnerabilityCVE-2026-43502

Stack buffer overflow in WAD

FortiOS explicit proxy WAD daemon stack buffer overflow (CVSS 5.1) allows code execution only with Kerberos and SOCKS configured.

Fortinet advisory FG-IR-26-161 describes a stack-based buffer overflow (CWE-121) in the WAD daemon of FortiOS explicit proxy, scored CVSSv3 5.1. Exploitation requires an attacker able to bypass stack protection and ASLR, and the explicit proxy must be configured with Kerberos authentication and SOCKS enabled. If successful, it yields arbitrary code or command execution in the WAD daemon context via crafted sockets. No exploitation is reported in the advisory.

Fortinet PSIRT · Aug 12, 2026Advisory

ZDI-26-636: Oracle Outside In Technology PostScript File Parsing Heap-based Buffer Overflow Remote Code Execution Vulnerability

ZDI disclosed a heap-based buffer overflow in Oracle Outside In Technology's PostScript parsing (CVE-2026-60412) enabling user-triggered remote code execution.

Zero Day Initiative published ZDI-26-636, a CVSS 7.8 heap-based buffer overflow in PostScript file parsing within Oracle Outside In Technology. Remote attackers can execute arbitrary code when the target opens a malicious file or visits a malicious page, making user interaction a requirement. The vulnerability is tracked as CVE-2026-60412. The advisory reports no exploitation.

ZDI-26-575: Linux Kernel Net Scheduler Packet Classifier API Time-Of-Check Time-Of-Use Local Privilege Escalation Vulnerability

ZDI publishes ZDI-26-575, a CVSS 7.5 TOCTOU local privilege escalation in the Linux kernel net scheduler packet classifier API.

The Zero Day Initiative disclosed a time-of-check time-of-use flaw in the Linux kernel's net scheduler packet classifier API that permits local privilege escalation. Exploitation requires the attacker to first execute high-privileged code on the target system. ZDI assigned a CVSS rating of 7.5; no CVE id is provided in the text.

ZDI Published Advisories · Aug 13, 2026Advisory1

ZDI-26-587: Ashlar-Vellum Cobalt VS File Parsing Heap-based Buffer Overflow Remote Code Execution Vulnerability

ZDI advisory ZDI-26-587 details a heap-based buffer overflow RCE (CVE-2026-19781, CVSS 7.8) in Ashlar-Vellum Cobalt VS file parsing, requiring user interaction.

The Zero Day Initiative released advisory ZDI-26-587 covering a heap-based buffer overflow in Ashlar-Vellum Cobalt's VS file parsing. A remote attacker can execute arbitrary code when the target opens a malicious file or visits a crafted page. ZDI rated the vulnerability CVSS 7.8 and assigned CVE-2026-19781.