Next cycleWhy this label: EPSS 3.3%, added 38 days ago

CVE-2025-39682Linux Kernel Improper Check for Unusual or Exceptional Conditions 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: 3.3%, higher than 88% of scored CVEs (Oct 25, 2026)
Weakness: CWE-754 Improper Exception Checks

What CISA says

Linux Kernel contains an improper check for unusual or exceptional conditions vulnerability in the TLS receive path which allows a zero-length record retrieved from the rx_list to bypass the intended recvmsg() record-type handling, potentially causing subsequent TLS records to be processed using incorrect zero-copy and queuing assumptions. The impacted product(s) could be end-of-life (EoL) and/or end-of-service (EoS). Users are advised to discontinue use and/or transition to a supported version.

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.