PoC Released for DirtyDecrypt Linux Kernel Vulnerability

Proof-of-concept (PoC) code is now available for another Linux kernel vulnerability that could allow attackers to elevate their privileges to root. Dubbed DirtyDecrypt (aka DirtyCBC), the exploit comes from the V12 security team, which discovered it earlier this month, after fixes were rolled out in April. The V12 team has not shared a CVE identifier for the security defect, but noted that it is a missing copy-on-write (COW) guard in the rxgk_decrypt_skb component of the RxGK subsystem. RxGK is a security class for the RxRPC network protocol used by the Andrew File System (AFS) and OpenAFS, which relies on the GSSAPI framework to provide authentication, confidentiality, and integrity protection. Due to the missing COW guard, oversized response authenticators are accepted, which results in data being written to the memory of privileged processes or to the page cache of privileged files, such as SUID binaries, Moselwal notes.    As Tharros Labs senior principal vulnerability analyst Will Dormann points out, the underlying issue could be CVE-2026-31635 (CVSS score of 7.5), a Linux kernel vulnerability disclosed on April 24, when patches were rolled out for mainline Linux builds. DirtyDecrypt only affects distributions that have CONFIG_RXGK compiled in and enabled, such as Arch Linux, Fedora, and openSUSE. In container platforms, all worker nodes running a vulnerable distribution could provide attackers with a path to escape the pod, Moselwal says. According to V12, the flaw is a variant of the recently identified CopyFail, DirtyFrag, and Fragnesia Linux kernel bugs, all of which grant root access on vulnerable systems. Disclosed last week and officially tracked as CVE-2026-46300, Fragnesia affects the XFRM ESP-in-TCP subsystem. It allows attackers to overwrite sensitive system files and gain root privileges. The Dirty Frag exploit published earlier this month chains two vulnerabilities in the Linux kernel, including one that affects the RxRPC component, to elevate privileges to root. Copy Fail, which was disclosed in late April, enables an attacker to modify the in-memory copies of setuid-root binaries, providing root shell access. Threat actors started exploiting it shortly after disclosure. Related: Researcher Drops MiniPlasma Windows Exploit for Unpatched 2020 CVE Related: Exploitation of Critical NGINX Vulnerability Begins Related: Google Detects First AI-Generated Zero-Day Exploit Related: Over 40,000 Servers Compromised in Ongoing cPanel Exploitation WRITTEN BY Ionut Arghire Ionut Arghire is an international correspondent for SecurityWeek. More from Ionut Arghire First Shai-Hulud Worm Clones Emerge Exploitation of Critical NGINX Vulnerability Begins PoC Code Published for Critical NGINX Vulnerability OpenAI Hit by TanStack Supply Chain Attack TeamPCP Ups the Game, Releases Shai-Hulud Worm’s Source Code Chrome 148 Update Patches Critical Vulnerabilities Chinese APTs Expand Targets, Update Backdoors in Recent Campaigns F5 Patches Over 50 Vulnerabilities Latest News B1ack’s Stash Marketplace Gives Away 4.6 Million Stolen Credit Cards Cyber Resilience is the New Business Continuity Plan 201 Arrested in Crackdown on Cybercrime in Middle East, North Africa Critical Vulnerability Exposes Industrial Robot Fleets to Hacking Millions Impacted Across Several US Healthcare Data Breaches ‘Claw Chain’ OpenClaw Flaws Allow Sandbox Escape, Backdoor Delivery 7-Eleven Data Breach Confirmed After ShinyHunters Ransom Demand Researcher Drops MiniPlasma Windows Exploit for Unpatched 2020 CVE Trending Webinar: Third-Party Risk In Practice June 4, 2026 Organizations are investing heavily in third-party risk management, but breaches, delays, and blind spots continue to persist. Join this live webinar as we examine the gap between how organizations think their third-party risk programs are performing and what’s actually happening in practice. Register Virtual Event: Threat Detection And Incident Response Summit May 20, 2026 Delve into big-picture strategies to reduce attack surfaces, improve patch management, conduct post-incident forensics, and tools and tricks needed in a modern organization. Register People on the Move Tim Byrd has been appointed Chief Information Security Officer at First Citizens Bank. IRONSCALES has named Steve McKenzie as Chief Operating Officer. Silvio Pappalardo has joined AuthMind as Chief Revenue Officer. More People On The Move Expert Insights Cyber Resilience Is The New Business Continuity Plan The organizations best prepared to face disruption are those that align security, continuity and risk management around what the business cannot afford to lose. (Steve Durbin) Enhancing Data Center Security Without Sacrificing Performance For AI data centers, where the stakes are the highest and performance constraints are the tightest, security and performance are no longer a zero-sum game. (Nadir Izrael) Is The SOC Obsolete, And We Just Haven’t Admitted It Yet? Many AI-first enterprises have already embraced sovereign architectures for general AI initiatives; cybersecurity—and the SOC—should be next. (Danelle Au) The Mythos Moment: Enterprises Must Fight Agents With Agents Only with the right platform and an agentic, AI-driven defense, will enterprises be able to protect themselves in the agentic era. (Etay Maor) Why Cybersecurity Must Rethink Defense In The Age Of Autonomous Agents From autonomous code generation to decision-making systems that initiate actions without human intervention, the industry is entering a new phase. (Torsten George) Flipboard Reddit Whatsapp Email