Linux kernel

Rust Researcher Builds AI Pipeline to Test 900 Vulnerability Hypotheses Across Crates and Linux Kernel

Sergey Gordeychik developed the rust-in-peace research harness that combines multiple LLM agents, traditional SAST tools, and dynamic verification to hunt for memory-safety, logic, and API misuse issues in Rust code. The system generates independent hypotheses, attempts to refute them with separate agents, then validates survivors through fuzzing, protocol tests, or container execution. Starting from the Damn Vulnerable Rust Application, the pipeline was expanded to popular crates including x509-parser, h2, and lopdf, ultimately producing a Linux kernel patch. Experiments showed that three parallel analysis passes yielded 20 confirmed findings after triage, with nine appearing in all passes. The work also highlighted how models can produce convincing but false positives when context such as dependency checks or call order is missing. Gordeychik presented the approach at ZeroNights under the title Rust in Peace: How to Raise Your Own Pet Mythos.

CISA Adds Three Actively Exploited Linux Kernel Vulnerabilities to KEV Catalog

The U.S. Cybersecurity and Infrastructure Security Agency has added three vulnerabilities affecting the Linux Kernel to its Known Exploited Vulnerabilities catalog. The flaws, identified as CVE-2025-39682, CVE-2026-53266, and CVE-2025-39964, are confirmed to be under active exploitation in the wild. CISA is directing all federal agencies to apply patches immediately and to search for indicators of compromise. The vulnerabilities impact the kernel's kTLS TLS processing, the ebtables network bridge component, and the AF_ALG cryptographic interface. Each issue can lead to memory corruption or inconsistent internal state that attackers may leverage for privilege escalation or remote code execution.

CISA Adds Linux Kernel Frag Gap Flaw and Two Other Exploited Vulnerabilities to KEV Catalog

The US Cybersecurity and Infrastructure Security Agency (CISA) added three vulnerabilities to its Known Exploited Vulnerabilities (KEV) catalog on August 27, 2026. One of the entries is CVE-2026-53362, a high-severity privilege escalation issue in the Linux kernel also known as Frag Gap. The flaw stems from an out-of-bounds write when generating IPv6 packets, allowing a low-privileged user to obtain root access. The Linux Kernel Organization assigned it a CVSS v3.1 base score of 7.8 and rated it High severity, with public exploit code already available. Federal agencies must remediate CVE-2026-53362 and CVE-2023-49105 by the August 30 deadline. The advisory underscores ongoing exploitation of these issues in the wild.

CISA Adds Six Actively Exploited Vulnerabilities to KEV Catalog Including Citrix NetScaler, Linux Kernel and Microsoft SQL Server Flaws

On August 26, 2026, CISA added six vulnerabilities to its Known Exploited Vulnerabilities catalog, signaling confirmed active exploitation and requiring immediate remediation priority. The batch includes a recent memory corruption issue in Citrix NetScaler ADC and NetScaler Gateway tracked as CVE-2026-8452, along with five older flaws affecting Microsoft SQL Server, the Linux kernel, Ajax.NET Professional, Red Hat libuser, and Red Hat ABRT. Citrix released patches for the NetScaler vulnerability on June 30, 2026, while CISA set an August 29, 2026 deadline for federal agencies. Real-world attacks have already deployed web shells and performed reconnaissance after successful exploitation of the Citrix appliance. The remaining CVEs enable remote code execution, local privilege escalation, and denial-of-service conditions across widely deployed enterprise technologies.

CISA Adds Six Known Exploited Vulnerabilities Affecting NetScaler ADC, Linux Kernel and Microsoft SQL Server to KEV Catalog

The U.S. Cybersecurity and Infrastructure Security Agency has added six vulnerabilities to its Known Exploited Vulnerabilities catalog after confirming active exploitation in the wild. One of the flaws, CVE-2026-8452, affects Citrix NetScaler ADC and NetScaler Gateway products and can trigger denial-of-service conditions under specific configurations. The remaining five issues, disclosed between 2015 and 2022, impact the Linux Kernel, Red Hat Automatic Bug Reporting Tool, and the libuser library. Exploitation of these older flaws can allow local attackers to escalate privileges or corrupt password files. Organizations are urged to apply available patches and verify configurations immediately.

Zapscape Flaw in KVM Breaks Nested Virtualization Isolation Allowing L1 Guest Root Code Execution on Linux Host

The Zapscape vulnerability (CVE-2026-64561) affects KVM/x86 in the Linux kernel and enables an attacker with kernel privileges inside an L1 virtual machine to escape to the host and execute code as root. The flaw occurs in the shadow MMU when handling page faults for nested guests, specifically due to an incorrect order of stale root condition checks that leads to a use-after-free condition. This weakens the isolation between the host and L1 guests precisely when nested virtualization is enabled for potentially untrusted tenants. A public proof-of-concept demonstrates the escape by creating a file named /Zapscape owned by root on the host. The issue impacts Linux kernels starting from version 5.9, with fixes already merged into stable branches including 6.6.148, 6.12.101, 6.18.42, 7.1.6 and 7.2 rc5. On Intel systems the attack requires EPT page walk lengths 4 and 5 to be exposed to the L1 guest, while no equivalent condition is documented for AMD. Organizations are advised to apply patches promptly or disable nested virtualization for untrusted workloads.