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Chaotic Eclipse Releases Crowdstrike Falcon ZeroDay FalconFlank

Researcher Chaotic Eclipse released FalconFlank, a PoC zero-day privilege escalation exploit against CrowdStrike Falcon's Microsoft Office macro removal feature.

Security researcher Chaotic Eclipse (also known as Nightmare Eclipse) published FalconFlank, a proof-of-concept zero-day exploit for a privilege escalation flaw in CrowdStrike Falcon Sensor. It abuses the Microsoft Office file malicious macro removal remediation feature, which runs with high privileges, and works on fully updated Windows 11 25H2 and Windows Server 2025 with Falcon Phase 3 Optimal Protection. CrowdStrike says it is investigating and advises customers to disable the Microsoft Office File Suspicious Macro Removal Windows policy. The same researcher recently released zero-day PoCs against Kaspersky Endpoint Security (HardBreacher) and Avast Antivirus (PrettyPrague), the latter dumping the SAM database for a SYSTEM shell.

Security Affairs · 7d agoExploit / PoC1· 1 read

Chaotic Eclipse Releases GenDigital Avast Antivirus ZeroDay PrettyPrague

Researcher Chaotic Eclipse released PrettyPrague, a PoC zero-day privilege escalation exploit against fully patched GenDigital Avast Antivirus.

Security researcher Chaotic Eclipse (also known as INFINITE NIGHTMARE or MSNightmare) published a PoC named PrettyPrague exploiting a zero-day privilege escalation flaw in Avast Antivirus. The PoC abuses a flaw in the Avast Sandbox to dump the Windows SAM database and spawn a SYSTEM-level shell, reportedly working on fully patched Avast and patched Windows 11 25H2. The researcher believes the flaw may also affect other GenDigital products such as AVG and Norton. It follows his recent HardBreacher PoC for a Kaspersky Endpoint Security privilege escalation flaw.

Security Affairs · 15d agoExploit / PoC

Fortinet Confirms Critical Zero Day

Fortinet has confirmed a critical zero-day vulnerability; the available headline provides no product, CVE, or exploitation details.

Infosecurity Magazine's headline states that Fortinet has confirmed a critical zero-day vulnerability. The available source text contains no additional details on affected products, CVE identifiers, exploitation status, or available fixes. Defenders should treat specifics as unconfirmed pending a vendor advisory.

Infosecurity Magazine · Aug 16, 2026Exploit / PoC in the wild

Metabase Zero-Day Exploited in Wild Allows Admin Access Without Authentication

Metabase warns an actively exploited zero-day (CVE-2026-72898, CVSS 10.0) grants unauthenticated admin access; Framework, n8n, and Kilo Code disclosed data exposure.

Metabase disclosed a maximum-severity SQL injection affecting versions x.58 through x.63 that lets unauthenticated attackers inject SQL via the /api/session/reset_password endpoint and gain administrator access to Metabase instances. Metabase Cloud was attacked, patches were released, and CISA added CVE-2026-72898 to the KEV catalog with a federal remediation deadline of August 14, 2026. Downstream victims include Framework (customer names, IPs, addresses, phone numbers, and emails accessed), n8n (136 customer records, five with bcrypt-hashed passwords), and Kilo Code (Slack access tokens). Wiz estimates roughly 13% of cloud environments run self-hosted Metabase, with about 2,500 instances internet-accessible.

The Hacker News · Aug 12, 2026Exploit / PoC in the wildCVE-2026-72898CVE-2023-38646

Lazarus Exploits Windows Zero-Day to Gain SYSTEM Access and Deploy Backdoor

Lazarus exploits Windows AFD.sys zero-day CVE-2026-68820 in Operation Dream Job to deploy Troy backdoor at defense firms.

Check Point attributes Operation Dream Job attacks to Lazarus Group exploiting CVE-2026-68820 (CVSS 7.0), a privilege escalation flaw in Windows AFD.sys patched in August 2026 Patch Tuesday. The campaign targets defense and aerospace firms in France, Germany, Brazil, and India via trojanized PDF viewers and DLL side-loading, deploying backdoors Troy, ForestTiger, and the FudModule 3.1 kernel rootkit. Attackers also compromise WordPress, SharePoint, and Roundcube servers as C2, using CVE-2025-49113 and the RelayShell PHP web shell.

The Hacker News · Aug 15, 2026Threat actor in the wildCVE-2026-68820CVE-2025-491132

GeoServer Zero-Day Targeted in Active Exploitation Attempts, Can Lead to RCE

A CVSS 9.8 SQL injection zero-day in GeoServer's PostGIS datastore enables RCE and drew active exploitation; fixes shipped in versions 3.0.1, 2.28.5, 2.27.6.

A SQL injection flaw in GeoServer's jsonArrayContains function within the GeoTools PostGIS datastore (GHSA-mqjf-5f49-2fjh, CVSS 9.8) was disclosed August 12, 2026, and saw hundreds of exploitation attempts within hours per watchTowr. An attacker-controlled value is interpolated into a PostgreSQL jsonb_path_exists() expression without escaping; with superuser or pg_execute_server_program privileges it escalates to OS command execution via WFS 1.0. GeoServer released versions 3.0.1, 2.28.5, and 2.27.6, and the flaw is a regression of CVE-2023-25158. GeoServer has a history of mass exploitation, including CVE-2024-36401 used for botnets and proxies.

The Hacker News · Aug 17, 2026Exploit / PoC in the wildCVE-2024-36401CVE-2023-25158CVE-2023-251571

What Zero-Day Response Should Be in the Post-Mythos Era

Picus Security outlines a zero-day response playbook where defenders simulate exploit technique chains before public PoCs exist.

The article uses PaperCut NG/MF's August incident — exploitation in the wild before any patch, with the first emergency fix bypassed the same day and a third landing September 1 — as the template for AI-accelerated vulnerability response. It walks through a hypothetical CVE-2026-1001 (explicitly made up) to argue defenders should map CVEs to ATT&CK technique chains and simulate them against NGFW, WAF, EDR, endpoint hardening, and SIEM controls within minutes of disclosure. It notes disclosure-to-exploitation time has fallen from 21.5 days to hours.

BleepingComputer · 1d agoResearch in the wildCVE-2026-1001

Serial Microsoft 0-day hunter drops yet another Defender exploit

Researcher Nightmare Eclipse released ShieldCrash, a Microsoft Defender zero-day PoC that bypasses September patches and reads files as SYSTEM.

Zero-day researcher Nightmare Eclipse (MSNightmare) published ShieldCrash, their 11th Microsoft zero-day, a proof-of-concept bypass of the ShieldBreak patch (CVE-2026-69414), which itself had bypassed the fix for RoguePlanet (CVE-2026-50656). ShieldCrash works on Windows 10, Windows 11, and Windows Server systems that have applied the September 2026 patches and allows arbitrary file reads as SYSTEM, though not arbitrary writes or a full SYSTEM shell. Microsoft has not said when it plans to patch the issue. The researcher recently also released zero-days affecting CrowdStrike Falcon (FalconFlank), Kaspersky endpoint antivirus (HardBreacher, patched), and Gen Digital's Avast (PrettyPrague).

The Register · Security · 7d agoExploit / PoCCVE-2026-69414CVE-2026-50656

Nightmare Eclipse Drops CrowdStrike, Nvidia, Avast Zero-Day Exploits

Researcher Nightmare Eclipse released working zero-day PoCs for Avast, CrowdStrike Falcon, and Nvidia, prompting a Gen patch, CrowdStrike mitigation, and Nvidia investigation.

Security researcher Nightmare Eclipse released three zero-day exploits within a short window: PrettyPrague targeting the Avast sandbox for full system privileges (possibly affecting other GenDigital products including AVG and Norton), FalconFlank exploiting CrowdStrike Falcon Sensor's Office malicious macros remediation feature for privilege escalation, and GreenSection targeting an out-of-bounds memory write in a shared global memory section used by Nvidia user-mode components. GenDigital said it has fixed the Avast issue; CrowdStrike advised disabling the Microsoft Office File Suspicious Macro Removal policy setting; Nvidia said it is actively investigating the PoC. Kevin Beaumont reported that the Avast, CrowdStrike, and Kaspersky exploits work. The researcher previously released the HardBreacher privilege escalation zero-day in Kaspersky endpoint security, patched August 31.

SecurityWeek · 9d agoExploit / PoC

ShieldBreak Zero-Day PoC Claims Microsoft Defender Patch Bypass With SYSTEM Access

Researcher Chaotic Eclipse released ShieldBreak PoC, a claimed patch bypass for Microsoft Defender flaw CVE-2026-50656, now tracked as CVE-2026-69414.

Researcher Chaotic Eclipse released a PoC for ShieldBreak, a claimed full patch bypass of Microsoft Defender flaw CVE-2026-50656 (RoguePlanet), which can yield SYSTEM privileges. Independent researchers Kevin Beaumont and Will Dormann validated the exploit on Windows 11 25H2 and Windows Server 2025, noting it requires Defender to be enabled. Microsoft assigned CVE-2026-69414 (CVSS 7.8) with an 'Exploitation More Likely' assessment and is investigating, but has not yet released a patch. The article also notes CISA's KEV addition of the actively exploited Windows AFD.sys flaw CVE-2026-68820.

The Hacker News · Aug 17, 2026Exploit / PoCCVE-2026-50656CVE-2026-62832CVE-2026-68820+2 CVEs

Zero-Day Dominance: How Akamai Defends Before the Industry Discloses

Akamai published vendor marketing on how its platform defends customers against zero-day exploits before industry-wide disclosure.

Akamai published a blog post titled 'Zero-Day Dominance: How Akamai Defends Before the Industry Discloses'; no article body text was available. Based on the title, the piece promotes Akamai's capabilities for protecting customers from zero-day exploits ahead of public disclosure. No specific vulnerabilities, CVEs, incidents, or customers are identified.

Akamai Blog · 19d agoIndustry

Google warns of new Chrome zero-day bug exploited in attacks

Google patched 230 vulnerabilities, including the seventh actively exploited Chrome zero-day of 2026.

Google released fixes for 230 vulnerabilities on Tuesday, including a Chrome zero-day that is being actively exploited in attacks. This is the seventh actively exploited Chrome zero-day patched since the start of 2026.

BleepingComputer · 7d agoExploit / PoC in the wild

Adobe Commerce Zero-Day Exploited to Backdoor Online Stores

Sansec found attackers exploiting an Adobe Commerce/Magento zero-day (StyleSmuggler) since September 4 to deploy Rust backdoors on online stores.

Threat actors are actively exploiting a zero-day RCE in Adobe Commerce and Magento 2.4.7-2.4.9, injecting PHP code via generated failure reports and executing it through Magento's payment-failure email, with no user interaction required. Exploitation began September 4 and succeeds even against stores running the July and August 2026 patches; the Rust backdoor disguises itself as kworker/u:8:0 or fc-cache and hides C&C communication inside fake NTP replies. Adobe's September 8 Patch Tuesday updates may not include a StyleSmuggler fix.

SecurityWeek · 9d agoExploit / PoC in the wild

PaperCut Zero-Day Exploited in Attacks, Affecting All NG and MF Versions

PaperCut warns of actively exploited zero-day RCE chain CVE-2026-81578 and CVE-2026-82078 affecting all PaperCut NG and MF versions.

PaperCut alerted customers that attackers are actively exploiting a zero-day affecting all versions of PaperCut NG and MF print management software, with confirmed customer incidents and an ongoing investigation. Emergency patches were released for v25 and v26, and the flaw was later identified as an exploitation chain of CVE-2026-81578 and CVE-2026-82078 enabling remote code execution. Shared IoCs include suspicious post-exploitation activity from pc-app.exe and missing, truncated or deleted server.log files with specific database errors. Users with internet-exposed PaperCut Application Servers are urged to immediately restrict access to trusted IPs; in 2023, CVE-2023-27350 (CVSS 9.8) in the same products was exploited by Lace Tempest to deliver Cl0p and LockBit ransomware.

The Hacker News · 16d agoExploit / PoC in the wildCVE-2026-81578CVE-2026-82078CVE-2023-273501

PaperCut Zero-Day: Active Exploitation and Pre-Auth RCE

PaperCut NG/MF hit by a pre-auth RCE zero-day under active exploitation; Huntress reproduced the chain and urged immediate patching.

Huntress reports active exploitation of a zero-day in PaperCut NG and PaperCut MF, and says it reproduced a pre-authentication remote code execution chain. The flaw allows unauthenticated attackers to execute code on exposed PaperCut servers. Huntress published urgent patching, exposure-reduction, and detection guidance. No CVE identifier was provided in the announcement.

Huntress · 19d agoExploit / PoC in the wild

Researcher Publishes CrowdStrike Privilege Escalation Zero Day

Researcher NightmareEclipse published FalconFlank, a zero-day local privilege escalation in CrowdStrike Falcon Sensor abusing its Office malicious macro remediation feature.

A researcher known as Nightmare Eclipse published details of FalconFlank, a zero-day privilege escalation that abuses the Microsoft Office malicious macro removal feature in CrowdStrike Falcon Sensor, verified working on fully updated Windows 11 25H2 and Windows Server 2025 with Falcon Phase 3 Optimal Protection. CrowdStrike urged customers to disable the Office File Suspicious Macro Removal policy while it investigates, noting customers remain protected via Cloud Anti-malware for Microsoft Office Files; no CVE has been assigned. The same researcher previously released the Exploitarium dump of over 30 PoC exploits, and researcher Kevin Beaumont confirmed FalconFlank works.

Infosecurity Magazine · 9d agoExploit / PoC

Re: Retrospective by 'gpg.fail' authors

GPG exploitation talk author clarifies a format-string 0day enabling code execution via printf %n writes and a polyglot PEM certificate payload.

Lexi Groves, author of the gpg.fail talk, clarified on oss-security that the first finding was an actual zero-day: a classic printf injection using %n for memory writes, with multiple X.509 certificates in one PEM file to re-enter and defeat ASLR before calling execv@plt. The payload executed the certificate itself, a polyglot file made by inserting a shebang and bash command into the PEM. A second finding was hash-collided by another party before the author could exploit it.

oss-securityupdated · 4h agofirst · 20h agoResearch 8 sources

OpenAI says GPT-6 Astra can find zero-days, but is also harder to monitor

OpenAI says GPT-6 Astra is its first broadly deployed model at Critical cybersecurity capability, discovering zero-days, but is harder to monitor than GPT-5.6 Sol.

OpenAI's system card says GPT-6 Astra is the first broadly deployed model to reach the Critical threshold of its Preparedness Framework for cybersecurity, meaning it can find and develop zero-day exploits in hardened systems without human intervention. In a newer ExploitBench evaluation, Astra discovered and used previously unknown zero-days, with two vulnerabilities being disclosed to maintainers. Astra produced 34 severity-3+ misalignment flags versus 73 for GPT-5.6 Sol, and indirect prompt injection robustness rose from 96.23% to 99.79%. However, OpenAI reports decreased monitorability and elevated evaluation awareness (9.6% of trajectories vs 2.8%), though it found no evidence of steganographic reasoning.

BleepingComputer · 8d agoAI safety & security1

⚡ Weekly Recap: Chrome 0-Day, Router Hijacks, Coder Supply Chain Attack and More

Weekly recap: actively exploited Chrome V8 zero-day, MikroTik RouterOS zero-day chain, Magento StyleSmuggler backdoor, and critical N-able N-central flaws.

Google patched an actively exploited Chrome V8 type confusion zero-day, CVE-2026-85046 (CVSS 8.8), the sixth exploited Chrome zero-day of 2026. CERT Polska warned of the MikroTrick exploit chain (CVE-2026-67276 and CVE-2026-86060, CVSS 9.2) giving unauthenticated full control of MikroTik RouterOS devices via SSH, observed since September 2. Sansec disclosed the StyleSmuggler Magento/Adobe Commerce zero-day used since September 4 to inject a Rust backdoor into online stores, while N-able patched three critical N-central flaws (CVE-2026-86206, CVE-2026-86207, and CVE-2026-86218, CVSS 10.0) with Huntress observing likely exploitation. Elastic and Morphisec also detailed RevStealer, an information stealer spread via game cheats and a fake Claude Desktop app.

The Hacker News · 9d agoExploit / PoC in the wildCVE-2026-85046CVE-2026-86206CVE-2026-86207+7 CVEs

The August 2026 Security Update Review

ZDI's August 2026 review covers a smaller-but-still-huge Microsoft and Adobe patch batch, with Adobe shipping 51 CVEs across five bulletins.

The Zero Day Initiative's August 2026 Security Update Review covers the latest Adobe and Microsoft patches. Adobe released five bulletins addressing 51 unique CVEs. The release is smaller than July's but still large by historical standards, which ZDI notes reflects a 'new normal' in patch density.

Zero Day Initiative Blog · Aug 11, 2026Vulnerability1

ZeroTokens Phishing Platform Steers Attacks in Real Time

ZeroTokens phishing platform hands operators live control of victim sessions in ongoing attacks targeting 53 financial brands.

ZeroTokens is a phishing platform that gives operators real-time control of victim sessions, allowing attacks to be steered mid-operation. The platform is being used in campaigns targeting 53 financial brands. Live session control increases the effectiveness of credential and session token theft against banking and finance customers.

Infosecurity Magazine · 22d agoPhishing & fraud in the wild

FalconFlank: CrowdStrike Falcon 0-Day PoC

A researcher published a working proof-of-concept for an alleged privilege escalation zero-day in CrowdStrike Falcon Sensor for Windows.

SOCRadar describes 'FalconFlank,' an alleged privilege escalation zero-day vulnerability in the CrowdStrike Falcon Sensor agent for Windows. The finding was published alongside working proof-of-concept code by a researcher. The available text does not state that exploitation has been observed in the wild, nor does it mention an assigned CVE.

SOCRadar · 13d agoVulnerability

ShieldBreak: New Windows Zero-Day Bypasses Microsoft’s RoguePlanet Patch

Researcher Chaotic Eclipse published a PoC bypassing Microsoft's CVE-2026-50656 Defender patch, enabling SYSTEM-level code execution on fully patched Windows systems.

Security researcher Chaotic Eclipse released a proof-of-concept for ShieldBreak, a Microsoft Defender zero-day that fully bypasses the patch for CVE-2026-50656 (RoguePlanet), a race condition in the Malware Protection Engine (mpengine.dll) allowing SYSTEM-level code execution. The PoC was tested on Windows 11 25H2 and Windows Server 2025 with a 100% success rate, and Windows 10 is also vulnerable though not supported by the PoC; the flaw may also leak 8 bytes of memory. Microsoft's MSRC had criticized the researcher's repeated uncoordinated disclosures, including YellowKey (BitLocker bypass), GreenPlasma, and LegacyHive (User Profile Service LPE).

Security Affairs · Aug 12, 2026Exploit / PoCCVE-2026-50656

PaperCut Zero-Day Under Active Attack: Emergency Patch Released

PaperCut warns that a zero-day in NG and MF print management products is being actively exploited, shipping emergency patches with no CVE assigned yet.

PaperCut Software confirmed active exploitation of a zero-day affecting PaperCut NG and MF, with confirmed customer incidents, and released emergency patches on Friday ahead of technical details or a CVE assignment. The company urges customers to restrict web access to trusted IP addresses, disconnect application servers from the internet, and watch for indicators including tampered or truncated server.log files, database error strings, and suspicious activity involving pc-app.exe. The article recalls the May 2023 exploitation of CVE-2023-27350 and CVE-2023-27351 by the financially motivated Lace Tempest group, a Clop ransomware RaaS affiliate, though no attacker attribution has been given for the current campaign.

Security Affairs · 18d agoExploit / PoC in the wildCVE-2023-27350CVE-2023-273511