Next cycleWhy this label: EPSS 1.6%, added 38 days ago

CVE-2025-39964Linux Kernel Race Condition Vulnerability

Product: Linux Kernel
Added to CISA KEV: September 18, 2026
Deadline for US federal agencies: September 21, 2026
Known ransomware use: Not known
EPSS, next 30 days: 1.6%, higher than 75% of scored CVEs (Oct 25, 2026)
Weakness: CWE-362

What CISA says

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.

What CISA asks you to do

Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

Sources

Also exploited recently

Data from CISA's Known Exploited Vulnerabilities catalog (public domain) and FIRST EPSS, refreshed hourly. Rheono did not find or test this vulnerability; this page summarizes public sources.