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

Required action (CISA's text)

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.

Description (NVD)

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.

SOURCES

• CISA KEVCISA Known Exploited Vulnerabilities catalog

Other Linux flaws

• CVE-2026-46300: Linux Kernel Missing Initialization of a Variable Vulnerability
• CVE-2026-53266: Linux Kernel Out-of-Bounds Write Vulnerability
• CVE-2025-39964: Linux Kernel Race Condition Vulnerability
• CVE-2026-53362: Linux Kernel Unspecified Vulnerability
• CVE-2022-0995: Linux Kernel Out-of-Bounds Write Vulnerability

Data from NVD, CISA KEV, FIRST EPSS and vendor advisories. Updated 10 Nov 2026.