Cybersecurity | KEV record | Draft staging record

Linux Kernel Race Condition Vulnerability

Linux Kernel contains a race condition vulnerability which allows concurrent writes to the same AF_ALG socket causing data to be unpredictably interleaved and creating inconsistencies in the socket's internal state.

Key points

• CVE: CVE-2025-39964
• Added to CISA KEV: 2026-09-18
• Federal remediation due date in the KEV record: 2026-09-21
• Known ransomware campaign use: Unknown

What to do

Apply the vendor fix or mitigation for this CVE, or discontinue use of the affected product where no fix exists. The full required action text is in the primary source record below.

Sources and provenance

Primary source: CISA Known Exploited Vulnerabilities Catalog. Structured record, tier computed in code: auto (reliability 95). This staging page renders a draft record from the Sprint 1 ingest spike; it is not a published story.