Is It On KEV?

Linux Kernel

YES - ON THE CISA KEV LIST
CVE-2025-39682

Linux Kernel Improper Check for Unusual or Exceptional Conditions Vulnerability

CISA catalog due date2026-09-21
51 days past due
EPSS exploit probability (next 30 days)3.3% · 89percentile
From CVE publication to KEV listing378 days (2025-09-05 → 2026-09-18)
Remediation window (KEV listing to due date)3 days
Days on the KEV list54 days
Date added to KEV2026-09-18
Known ransomware campaign useUnknown
VendorLinux
ProductKernel
Weaknesses (CWE)CWE-754

Linux: 32 entries (1.8% of all KEV entries are from this vendor); 9 added in 2026.

BOD 26-04 note: this is the date printed in the CISA catalog. A federal agency's actual deadline is set by its SSVC tier - Act (3 days), Attend (14 days), Track (60 days), or the next scheduled upgrade - counted from the KEV listing date or the date the vulnerability is identified in its environment, whichever comes first. Use the tier helper on each CVE page for your own window.

Your BOD 26-04 window (SSVC tier helper)

Your remediation window ends:

Description

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 (CISA)

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.

Notes

This vulnerability affects an open-source component, third-party library, protocol, or proprietary implementation that could be used by different products. For more information, please see: ; https://git.kernel.org/stable/c/2902c3ebcca52ca845c03182000e8d71d3a5196f; https://git.kernel.org/stable/c/c09dd3773b5950e9cfb6c9b9a5f6e36d06c62677; https://git.kernel.org/stable/c/3439c15ae91a517cf3c650ea15a8987699416ad9; https://git.kernel.org/stable/c/29c0ce3c8cdb6dc5d61139c937f34cb888a6f42e; https://git.kernel.org/stable/c/62708b9452f8eb77513115b17c4f8d1a22ebf843 ; BOD 26-04: https://www.cisa.gov/news-events/directives/bod-26-04-prioritizing-security-updates-based-risk ; Forensics Triage Requirements: https://www.cisa.gov/news-events/directives/bod-26-04-implementation-guidance-prioritizing-security-updates-based-risk ; https://nvd.nist.gov/vuln/detail/CVE-2025-39682

References

Other KEV entries for this vendor: Linux

Linux - Vendors with KEV entries

Go deeper

KEV deadlines are a governance problem as much as a patching one. TrebSec's AI governance packs help small teams document, assign, and evidence exactly this work.

AI Governance Policy Pack - $79 AI Vendor Workbook - $49 Both packs bundled - $99

Daily threat briefs at trebsec.com

Check another CVE