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ZDI-26-697: Linux Kernel NTFS3 Out-Of-Bounds Read Information Disclosure Vulnerability

ZDI-26-697: Linux Kernel NTFS3 out-of-bounds read rated CVSS 7.3 lets local low-privileged attackers disclose sensitive information.

ZDI advisory ZDI-26-697 describes an out-of-bounds read in the Linux Kernel NTFS3 driver rated CVSS 7.3. An attacker must first be able to execute low-privileged code on the target system to exploit the flaw. Successful exploitation leads to sensitive information disclosure. No CVE identifier is listed in the advisory.

USN-8514-2: OpenSSH vulnerability

Ubuntu backports an OpenSSH fix to older LTS releases for an scp flaw enabling setuid file placement and privilege escalation.

USN-8514-2 extends the USN-8514-1 OpenSSH fix to Ubuntu 14.04 LTS, 18.04 LTS, and 20.04 LTS. The flaw stems from incorrect file permission handling when downloading files as root using the legacy scp protocol without the preserve-mode option. An attacker could exploit this to install setuid or setgid files on the system, potentially leading to privilege escalation.

Backdoor Xz Utils Linux Open Source

Infosecurity Magazine covers the XZ Utils open-source backdoor, a malicious implant in liblzma that targeted OpenSSH on major Linux distributions.

The article covers the XZ Utils backdoor, a malicious implant introduced into the widely used open-source compression library. The compromised liblzma code manipulated functions used by OpenSSH, nearly reaching stable releases of major Linux distributions before discovery. The incident is a prominent example of software supply chain compromise targeting critical open-source infrastructure.

Infosecurity Magazine · Aug 17, 2026VulnerabilityCVE-2024-3094

PoisonedRefresh: A Fileless Linux Rootkit That Injects PHP Web Shells Into F5 BIG-IP APM Server Memory

Sophos details PoisonedRefresh, a fileless Linux rootkit that injects a memory-resident PHP web shell into F5 BIG-IP APM after exploitation of CVE-2025-53521.

On September 8, 2026, SophosLabs published an analysis of Linux/Agnt-IC (dubbed PoisonedRefresh by ESET) found in compromised F5 BIG-IP Access Policy Manager environments. Initial access leverages CVE-2025-53521, an unauthenticated RCE in BIG-IP APM when an access policy is configured on a virtual server; F5 confirmed exploitation and links the activity to cluster c05d5254, while Shadowserver observed 795 exposed vulnerable endpoints. A first stage hidden in a modified umount binary modifies /usr/sbin/httpd and SELinux configuration and embeds itself in BIG-IP upgrade images for persistence. The second-stage ELF intercepts __libc_start_main, hooks apr_dso_load, and injects a PHP web shell into libphp memory via mmap manipulation, leaving no disk artifacts, and exposes a /bin/bash shell via a local UNIX domain socket instead of a TCP port.

Security Affairs · 7d agoMalware in the wildCVE-2025-53521

Week in review: Salesforce and ServiceNow portals exposed for 17 months, exploited Metabase 0-day

Weekly digest: exploited Metabase zero-day breached Framework; Salesforce/ServiceNow portals read for 17 months; Microsoft patched 400+ flaws.

Help Net Security's week in review aggregates top stories: a 'City-Forum' campaign tracked by Reco has been pulling records from Salesforce and ServiceNow portals worldwide for 17 months, and Framework suffered a breach via an exploited Metabase zero-day exposing customer contact and IP data. It also covers Microsoft's August 2026 Patch Tuesday fixing 400+ flaws including exploited zero-day CVE-2026-68820, Cisco's fix for exploited firewall DoS bug CVE-2026-20349 (added to CISA KEV), and a second N-able N-central hotfix for actively exploited CVE-2026-18577. Other items include GitHub expanding Dependabot malware alerts to eight package ecosystems and EU AI Act enforcement beginning on 2 August 2026.

Help Net Security · Aug 16, 2026Industry in the wildCVE-2026-18577CVE-2026-68820CVE-2026-203491

DPRK APTs: Ted backdoor and curlRAT target South Korean media and automotive sectors

Rapid7 uncovered a DPRK-linked Linux toolkit using a HAProxy-embedded ted backdoor, SSH keylogger, and curlRAT against South Korean media and automotive firms.

Rapid7 Labs identified a previously undocumented framework attributed with medium confidence to DPRK actors, targeting South Korean automotive and media organizations likely since early 2025. The toolkit embeds a backdoor compiled into HAProxy 2.8.12 using its filter API, plus trojanized crond, agetty, atd, sshd, and polkitd, an SSH keylogger storing credentials under /var/lib/sshd/, and a curl-based RAT with a watchdog thread. It enables remote command execution, malicious script injection into served webpages (a watering-hole loop), credential harvesting, and long-term surveillance. Hardcoded C2s are associated with APT37 via ThreatFox, and exposed groupware portals and mail servers align with Kimsuky tradecraft; the initial access vector and any CVE remain unconfirmed.

Rapid7 Blog · 12d agoThreat actor in the wild1

Microsoft’s September 2026 Patch Tuesday addresses 964 CVEs (CVE-2026-81963, CVE-2026-85880)

Microsoft's September 2026 Patch Tuesday fixes a record 964 CVEs, including two zero-days actively exploited in the wild.

Microsoft patched a record 964 CVEs in its September 2026 Patch Tuesday release, with 101 rated critical and 824 rated important, making it the largest Patch Tuesday to date. The release includes fixes for two zero-days that were exploited in the wild, with CVE-2026-81963 and CVE-2026-85880 highlighted in the release. Affected products span Windows core components, Office, Exchange, .NET, Visual Studio, Active Directory services (including AD CS and AD FS) and numerous Azure services. Tenable notes the release surpasses July's as the biggest ever.

Tenable Blog · 8d agoVulnerability in the wildCVE-2026-81963CVE-2026-858801

VU#718077: UEFI Shell module embedded in SPI Flash can be used to bypass Secure Boot

CERT/CC details VU#718077: UEFI Shell embedded in SPI flash lets attackers bypass Secure Boot and execute pre-boot code; patches issued.

CERT/CC's VU#718077, reported by Eclypsium researcher Stas Lyakhov, describes how a UEFI Shell embedded in SPI flash can be abused by attackers who can modify UEFI boot configuration, creating multiple boot entries that bypass controls preventing the Shell from launching under Secure Boot. The Shell's dmem and mm commands allow arbitrary physical memory read/write, letting attackers overwrite Secure Boot values and execute unauthorized pre-boot code that can persist across reboots and OS reinstalls while degrading EDR effectiveness. AMI confirmed its Aptio UEFI BDS module is affected (CVE-2026-33197), and Cisco published an advisory for a variation affecting UCS Servers and UCS-based appliances (CVE-2026-20293). Firmware patches are being rolled out through OEM and IBV BIOS build pipelines.

APT36 Suspected in PATCHCORD Espionage Campaign Using Google Sheets C2

Acronis links the PATCHCORD espionage campaign targeting Afghan telecom and South Asian critical infrastructure to APT36 with moderate confidence.

Acronis Threat Research Unit documented PATCHCORD, a previously undocumented C/C++ backdoor delivered via fake VPN installers impersonating Afghan Telecom (AFTEL), which hijacks Edge, Chrome and Firefox shortcuts for persistence and executes in-memory shellcode. A related Go implant, SHEETCORD, abuses the Google Sheets API for per-victim C2 and was distributed via a domain impersonating India's National Informatics Centre, while a third tool, HACKERAI C2 Agent, uses GitHub Gists and shows signs of LLM-assisted coding. An exposed staging server revealed SuperShell, RAT frameworks, credential-harvesting tools and OpenSSH exploit code, and the researchers attribute the activity to APT36/Transparent Tribe at moderate confidence.

Security Affairs · Aug 16, 2026Threat actor in the wild

This Key Will Self-Destruct: An Open Standard for Revocable API Keys

SecurityWeek opinion piece proposes ORKS, an open standard adding issuer prefixes, discovery files, and unauthenticated revocation endpoints to make leaked API keys quickly revocable.

The article argues that plain API keys leak frequently yet lack any standardized revocation mechanism, unlike OAuth tokens which gained RFC 7009 revocation in 2013, and that GitHub's Secret Scanning Partner Program solves this only in a proprietary, invite-only way. The author proposes ORKS (Open Revocable Key Standard), with a draft spec on GitHub, built on four parts: keys embedding their issuer domain in a fixed prefix format, a discoverable /.well-known/api-key-config JSON file, unauthenticated revocation by possession of the full key, and declared constraints such as IP allowlists, expiry, scopes, and mTLS. An optional quarantine mode inspired by Toyota's andon cord restricts a reported key to read-only and throttled operation for a default 24-hour window before automatic revocation. The piece frames AI agents as making this urgent, since agents hold many credentials, can exfiltrate them via prompt injection, and can leak secrets into logs at machine speed.

SecurityWeek · 7d agoTools1

Gunra Ransomware Exploits Fortinet FortiOS, FortiProxy Flaws to Breach Networks

CISA, FBI, and South Korean agencies warn Gunra ransomware, with 51 victims since April 2025, exploits Fortinet flaws for double-extortion attacks on critical infrastructure.

CISA, the FBI, and South Korean agencies warned of Gunra ransomware attacks targeting healthcare, financial services, government, and professional services worldwide. The Conti-derived operation exploits internet-facing Fortinet FortiOS and FortiProxy flaws CVE-2024-55591 and CVE-2025-24472 for initial access, then deploys double extortion with Salsa20/ChaCha20 encryption and publishes non-payers on a leak site within five to seven days. Ransomware.Live lists 51 victims since April 2025, mostly in South Korea, Brazil, Spain, Thailand, and Hong Kong. The group uses Impacket tools for SMB lateral movement and NTDS credential dumping, tampers with VDI authentication to accept a designated OTP value to bypass MFA, and launched a RaaS affiliate program in January 2026 under the new alias Golden Community.

The Hacker News · Aug 12, 2026Ransomware in the wildCVE-2024-55591CVE-2025-24472

Hackers deploy Linux rootkit on F5 BIG-IP APM devices, hiding web shell in memory

Sophos analyzed a Linux rootkit, tracked as PoisonedRefresh, on hacked F5 BIG-IP APM devices hiding an in-memory web shell linked to exploited CVE-2025-53521.

Sophos and ESET analyzed an implant (named PoisonedRefresh by ESET) deployed on compromised F5 BIG-IP APM appliances, which serves enterprise, financial, government, and public sector deployments. The second-stage payload intercepts __libc_start_main, hooks Apache's APR module loader (apr_dso_load), RC4-encodes key strings, and rewrites PHP file reads in memory to embed a web shell inside legitimate scripts like apm_css.php3, full_wt.php3, and webtop_popup_css.php3, leaving on-disk files unchanged. A related installer component infects /usr/sbin/httpd, persists across BIG-IP upgrade images, modifies SELinux configuration, and deploys the payload. The malware also creates a Unix domain socket at /run/bigtlog.pipe that hands authenticated local connections to /bin/bash; F5 links the activity to CVE-2025-53521, an unauthenticated RCE in BIG-IP APM already exploited in the wild.

Help Net Security · 7d agoMalware in the wildCVE-2025-535211

Hackers breach F5 BIG-IP APM devices to deploy Linux rootkit

Sophos analyzed a Linux rootkit on F5 BIG-IP APM devices that injects a fileless PHP web shell, likely after CVE-2025-53521 exploitation.

Sophos analyzed a Linux rootkit targeting F5 BIG-IP APM environments, also tracked by ESET as PoisonedRefresh, which hijacks Apache's apr_dso_load module loader to inject a fileless PHP web shell into memory. The implant intercepts __libc_start_main, hides strings with RC4, creates a password-protected local UNIX socket backdoor for interactive Bash access, and persists across BIG-IP upgrade images while modifying SELinux configuration. It is likely a second-stage payload following exploitation of CVE-2025-53521, a critical RCE flaw F5 reclassified from a DoS issue in March. The ShadowServer Foundation tracked 795 F5 BIG-IP APM endpoints exposed online.

BleepingComputer · 8d agoMalware in the wildCVE-2025-53521

New Ted Backdoor Hides Inside Victims' Own HAProxy Builds to Intercept Web Traffic

Rapid7 found a new backdoor, ted, compiled into trojanized HAProxy at two South Korean organizations, with medium-confidence attribution to North Korean actors.

Rapid7 documented a previously undocumented Linux toolkit named ted compiled into the HAProxy load balancer binaries of two South Korean organizations in the automotive and media sectors. The implant intercepts web traffic, serves altered pages only to filtered visitors, and hides C2 exchanges from backend logs and HAProxy statistics; a companion RAT, curlRAT, beacons on a default 12-hour schedule. The toolkit also trojanizes crond, sshd, agetty, atd, and polkitd binaries and sanitizes logs and bash history. Rapid7 attributes the activity with medium confidence to North Korean state-sponsored actors, with domain infrastructure overlapping APT37 listings in maltrail and delivery resembling the Operation SyncHole campaign.

The Hacker News · 12d agoThreat actor in the wild

Researchers open-source a Wi-Fi cyber range for security training

NTNU and Aegean researchers open-source a software-emulated Wi-Fi cyber range using mac80211_hwsim with LLM-assisted scenario building.

Researchers from the Norwegian University of Science and Technology and the University of the Aegean published a design and prototype for a cyber range dedicated to IEEE 802.11 security training, emulating access points and clients with mac80211_hwsim, Linux namespaces, hostapd, wpa_supplicant, dnsmasq, and FreeRADIUS. The platform bundles Aircrack-ng, Wireshark, and custom tools WPAxFuzz and Bl0ck, and can convert plain-language scenario descriptions into deployable definitions via a locally hosted Llama model. A working prototype covering scenario creation and deployment is on GitHub; monitoring, access control, and orchestration zones remain future work.

Help Net Security · 23d agoTools1

iceener/files-stdio-mcp-server: sandbox escape in fs_search via a symlinked directory (recursive walker validates only the top level)

iceener/files-stdio-mcp-server allows a read-side sandbox escape: fs_search follows symlinked directories while the recursive walker validates confinement only at the top level.

A vulnerability report describes a read-side sandbox escape in iceener/files-stdio-mcp-server, an MCP server for text-based file access that explicitly promises 'Sandboxed filesystem access. Only these paths are available'. The fs_search tool can follow symlinked directories outside the allowed paths, and the recursive directory-listing walker used by fs_search (and by fs_read) validates confinement only at the top level. The same flaw affects fs_read's directory-listing walker. No CVE identifier was assigned in the provided report text.

oss-security · 6d agoVulnerability

ZDI-26-687: Linux Kernel Open vSwitch Flow Delete Use-After-Free Information Disclosure Vulnerability

ZDI discloses Linux Kernel Open vSwitch use-after-free (CVE-2026-80994) letting low-privileged local attackers disclose sensitive kernel information, CVSS 6.4.

ZDI-26-687 covers a use-after-free information disclosure vulnerability in the Linux Kernel's Open vSwitch flow deletion handling, tracked as CVE-2026-80994 with a CVSS rating of 6.4. Exploitation requires the ability to execute low-privileged code on the target system. The flaw allows local attackers to disclose sensitive information from affected installations.

12 Best Endpoint Encryption Software Compared (2026): Features & Pricing

2026 buying guide compares 12 endpoint encryption tools, framing paid products as management layers over free BitLocker and VeraCrypt engines.

An editorial comparison evaluates twelve endpoint encryption offerings, arguing that full-disk encryption itself is largely solved with free options like Microsoft BitLocker and open-source VeraCrypt. Paid products such as Sophos Central Device Encryption, Broadcom Symantec Endpoint Encryption, and Check Point Full Disk Encryption are positioned around management: central enforcement, recovery-key escrow, pre-boot authentication, and compliance evidence. The guide also warns against unmaintained tools like Rohos for business use and stresses operational concerns over cipher selection.

GBHackersupdated · 10h agofirst · 5d agoIndustry 14 sources

Stealth rootkit targeting F5 BIG-IP could expose enterprise identity gateways

Sophos analyzed a stealth Linux rootkit that hides a web shell in memory on compromised F5 BIG-IP APM identity gateways, evading file-based detection.

Sophos analyzed a second-stage Linux rootkit implant found in compromised F5 BIG-IP APM environments running Apache and PHP, linked to exploitation of CVE-2025-53521, an unauthenticated RCE. The implant hooks Apache's PHP-loading process and serves modified in-memory versions of three legitimate webtop PHP files (apm_css.php3, full_wt.php3, webtop_popup_css.php3), leaving on-disk files untouched so hashes and integrity checks pass. It also establishes access via an authenticated local UNIX socket that can provide an interactive /bin/bash session. Experts warn compromised APM appliances, which handle federated SSO and terminate TLS at enterprise perimeters, could enable SSO token theft and lateral movement to trusted downstream applications.

CSO Online · 6d agoMalware in the wildCVE-2025-53521

From Hypervisor to Container: Cloud Security Vulnerabilities, Defense Mechanisms, and Open Challenges

Survey of 120+ cloud security papers (2008-2025) reviews hypervisor and container isolation attacks, scoring defenses with the ADPO framework and CIA impact scale.

This survey reviews over 120 security publications from 2008 to 2025 on breaches of cloud isolation boundaries via virtual machines and containers. Threats examined include VM escape, VM hopping, CPU cache side-channels, container breakouts, vulnerable container images, and DDoS attacks. The authors introduce ADPO, a 0-3 scoring framework rating defenses on accuracy, deployment ease, performance impact, and operational overhead, plus a 1-5 CIA severity mapping for attack impact.

arXiv cs.CR · 1d agoResearch

TPMSpy: Validation of Measured Boot Systems by Low-Level Tracing of TPM Usage

Researchers present TPMSpy, a platform-agnostic method validating TPM Measured Boot via low-level tracing, finding inconsistent Linux systemd measurements that break remote attestation and LUKS decryption.

An arXiv paper (2609.05011) introduces TPMSpy, a method that analyzes virtualized system–TPM interactions to independently reconstruct and validate TPM Event Logs without relying on the quoting mechanism, applicable to open and closed systems and demonstrated on Linux and Windows. A longitudinal analysis of Linux systems running systemd versions 245–258 (2020–2025) found wide divergence in Measured Boot usage, undocumented behavioral changes, and no common usage pattern. The authors report inconsistent measurement of user-space systemd services, which prevents reliable remote attestation and LUKS disk decryption on affected systems.

arXiv cs.CR · 12d agoResearch

Linux Detection Engineering - Local Privilege Escalation

Elastic details a layered detection framework for Linux local privilege escalation, covering 2026's copy-on-write bug wave and LLM-assisted discovery.

Elastic Security Labs describes how most Linux local privilege escalations share a common host flow — an unprivileged process launched from a writable path becoming root — and proposes layered detections combining general outcome-based rules with per-technique rules in Elastic Defend and Auditd. It tracks 13 recent LPE disclosures, seven of which share a copy-on-write/zero-copy bug class, including Copy Fail, DirtyFrag, Fragnesia, DirtyDecrypt, DirtyClone, pedit COW, and RefluXFS. Qualys attributes RefluXFS to an LLM-assisted research effort with Anthropic using Claude Mythos Preview, and another bug is credited to an LLM-assisted workflow. Detection and endpoint rules are published in Elastic's detection-rules and protections-artifacts repositories.

Elastic Security Labs · 5d agoResearch

ZDI-26-623: Linux Kernel IPv6 Multicast Routing Use-After-Free Local Privilege Escalation Vulnerability

ZDI-26-623 details a use-after-free in Linux kernel IPv6 multicast routing enabling local privilege escalation, rated CVSS 8.8.

The Zero Day Initiative published ZDI-26-623 describing a use-after-free vulnerability in the Linux kernel's IPv6 multicast routing implementation. A local attacker who can execute low-privileged code on an affected installation can exploit the flaw to escalate privileges. ZDI assigned a CVSS rating of 8.8; the advisory does not name a CVE id or state that exploitation has been observed.

ZDI Published Advisories · 7d agoAdvisory

Parallels Desktop Flaw Lets Unprivileged Mac Users Gain Root Access

JFrog's 'ParaShells' research details CVE-2026-90894, a Parallels Desktop local privilege escalation letting unprivileged macOS users gain root via tar argument injection.

JFrog researcher Yuval Moravchick disclosed CVE-2026-90894 ('ParaShells'), a critical local privilege escalation flaw demonstrated against Parallels Desktop 26.4.0 build 57513 on Apple silicon. The world-writable /var/run/prl_disp_service.socket accepts connections from unsigned clients, and argument injection into a tar extraction command via the --use-compress-program option executes attacker-controlled code with root privileges. The attack needs no administrator permissions, running VM, or Parallels-signed client, and a one-line PoC yielded a root shell. Risk is highest on developer workstations, shared training systems, and enterprise Macs.

GBHackersupdated · 7h agofirst · 9h agoVulnerability 4 sourcesCVE-2026-90894

An Empirical Security Analysis of Open-Source Software Used in Onboard Satellite Systems

Study of 126 onboard satellite OSS repositories finds 2,827 security findings, 72% medium severity or higher, dominated by memory safety and code quality weaknesses.

Researchers performed an empirical security analysis of 126 public repositories of open-source software used in onboard satellite systems using SBOM generation, software composition analysis, static application security testing, infrastructure-as-code analysis, and secret scanning. After cleaning and deduplication the pipeline produced 2,827 findings, with medium-severity findings accounting for 49% and 72% classified medium or higher. A CWE-based taxonomy mapped all findings to eight weakness families, with Memory Safety and Code Quality dominating, followed by Input Validation and Injection. Project-developed code accounted for 81.4% of findings, though external dependency code remained relevant; findings do not establish mission-specific exploitability.

arXiv cs.CR · 2d agoResearch1

Keys to the Kingdom: Erlang/OTP SSH Vulnerability Analysis and Exploits Observed in the Wild

Attackers actively exploit CVE-2025-32433, a CVSS 10.0 unauthenticated RCE in Erlang/OTP SSH, heavily targeting OT and critical infrastructure networks.

CVE-2025-32433 enables unauthenticated RCE in Erlang/OTP's SSH daemon via SSH connection protocol messages (codes >= 80) processed before authentication, affecting versions before OTP-27.3.3, OTP-26.2.5.11 and OTP-25.3.2.20. Unit 42 recorded a spike in exploitation between May 1-9, 2025, with 70% of detections on firewalls protecting OT networks, disproportionately affecting healthcare, agriculture, media and high technology. Observed payloads bind TCP-connected shells or launch Bash reverse shells to hosts like 146.103.40.203:6667, with randomized DNS lookups under dns.outbound.watchtowr.com indicating OAST-driven blind RCE validation.

Palo Alto Unit 42 · Aug 17, 2026Exploit / PoC in the wildCVE-2025-32433

Notes on gotchas while migrating 35kb preprompts from Opus to self-hosted Ollama

Opinion piece urges migrating 35KB preprompts from Anthropic/OpenAI to self-hosted Ollama, citing session privacy risks and safety filters blocking security research.

The author documents gotchas migrating 35KB preprompts from Claude Opus to self-hosted Ollama, motivated by fears that frontier providers train on user sessions, citing the OpenAI Navier-Stokes controversy. The piece argues inference providers cannot audit their own retention or training pipelines and that only self-hosted hardware offers verifiable privacy. It also criticizes frontier safety filters for refusing vulnerability research tasks and calls for models that support exploitability testing in CI/CD pipelines.

Open-source secrets scanning tool Sift hunts credentials in Microsoft 365, Slack, and Jira

Stratus Security open-sourced Sift, a CLI secrets scanner covering Active Directory, SharePoint, Teams, Slack, Jira, and Confluence, outperforming Snaffler in benchmarks.

Stratus Security released Sift, a free open-source command line tool that hunts passwords, API keys, and sensitive data across local disks, Windows shares, Active Directory, SharePoint, OneDrive, Teams, Slack, Jira, and Confluence. In the firm's benchmarks, Sift scanned 250,000 files in 10.61 seconds versus Snaffler's 25.48 and averaged 92 MiB memory versus Snaffler's 337 MiB. Optional false-positive filtering runs through a local language model via Ollama, and scans write checkpoints so interrupted runs resume. The tool found thousands of credentials in Jira ticket comments that prior pentesting had missed.

Help Net Security · 14d agoTools

Linux Detection Engineering - Fileless Execution

Elastic Security Labs reproduces five Linux fileless execution patterns, including memfd_create staging and in-memory kernel module loads, and maps each to Elastic Defend rules.

Elastic Security Labs reproduced five Linux fileless execution patterns using its FENIX tooling: memfd_create staging, interpreter one-liners, deleted binaries, and in-memory kernel module loads. Each pattern is mapped to the Elastic Defend detection rules that catch it. The post is part of the team's ongoing Linux detection engineering series.

Elastic Security Labs · 15d agoResearch