CVE-2025-39682 — Linux Kernel Improper Check for Unusual or Exceptional Conditions Vulnerability

Impacted if

• Linux 6.0

over the network · no login

In the Linux kernel, the following vulnerability has been resolved: tls: fix handling of zero-length records on the rx_list Each recvmsg() call must process either - only contiguous DATA records (a

CISA Known Exploited Vulnerabilities

Added on 2026-09-18, federal remediation due 2026-09-21. 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.

Required action: 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.

First seen by AX-NEWS 19 Sep 2026, 06:24 UTC · latest story 13 Oct 2026, 00:00 UTC. Severity: NVD, or the CVE record while the NVD has not scored it. This product uses data from the NVD API but is not endorsed or certified by the NVD.