CVE-2026-74714 Linux CVE debrief

Who should care

Linux kernel developers, administrators, and users of affected Linux versions should assess exposure and apply patches or mitigations as necessary. This includes reviewing system configurations, verifying the integrity of affected systems, and monitoring for suspicious activity. Additionally, security teams and vulnerability management teams should prioritize patching and ensure that compensating controls are in place for exposed systems.

Why it matters

This vulnerability in the Linux kernel requires attention from developers, administrators, and users of affected versions to prevent potential system instability, unauthorized access, or privilege escalation. Verification of affected versions and application of patches are crucial.

• Potential system crashes or instability due to use-after-free errors.
• Possible elevation of privileges or unauthorized access.
• Required verification of affected versions and application of patches.
• Need for monitoring and incident response planning.

Technical summary

The vulnerability exists in the Linux kernel's bpf_iter_tcp_established_batch() function, where a use-after-free error occurs due to a race condition with TCP_NEW_SYN_RECV request_sock. This issue arises from incorrect reference count handling. The bpf_iter_tcp_established_batch() function uses plain sock_hold() while holding the bucket lock, assuming the lock guarantees sk_refcnt > 0. However, this assumption does not hold for request_sock, leading to a potential use-after-free error. Affected Linux kernel developers, administrators, and users should assess exposure and apply patches or mitigations as necessary.

Defensive priority

High

Recommended defensive actions

• Review and apply patches from Linux vendors for the affected versions.
• Restrict access to vulnerable systems and monitor for suspicious activity.
• Verify the integrity of affected systems and check for indicators of compromise.
• Perform vulnerability scanning to identify potentially affected systems.
• Implement compensating controls for exposed systems while remediation is scheduled and verified.
• Monitor relevant logs and detection systems for signs of exploitation.
• Track exceptions and retest remediated assets to ensure patch efficacy.

Evidence notes

The CVE record and source item provide details about the vulnerability, including its description and affected versions. However, the corpus does not establish specific exploitation or impact details, requiring verification from official sources.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.