CVE-2026-53182 Linux CVE debrief

Who should care

System administrators and security teams responsible for Linux kernel-based systems should be aware of this vulnerability. Given its HIGH severity and potential for exploitation, prioritizing patching or mitigation strategies is crucial. The vulnerability's impact is particularly significant for systems relying on the nl80211 component for wireless networking.

Technical summary

The vulnerability is located in the nl80211 component of the Linux kernel. Specifically, the nl80211_parse_rnr_elems() function stores the parsed element count in a u8-backed cfg80211_rnr_elems::cnt field. This count is used to size the flexible array allocation. The vulnerability allows for an out-of-bounds write when the count reaches 255, before incrementing it again. The fix involves rejecting nested NL80211_ATTR_EMA_RNR_ELEMS input once the count reaches 255. This change prevents potential buffer overflows and ensures the parser's alignment with the filled data structure.

Defensive priority

High priority should be given to patching or mitigating this vulnerability due to its HIGH CVSS score of 7.8 and the potential for exploitation. System administrators should review their Linux kernel versions and apply patches or updates as soon as possible.

Recommended defensive actions

• Apply patches or updates provided by the Linux kernel maintainers to address the vulnerability.
• Review system configurations and ensure that the nl80211 component is properly secured.
• Monitor system logs for potential exploitation attempts.
• Consider implementing compensating controls, such as network segmentation or access controls, to limit the impact of a potential exploit.
• Perform thorough vulnerability assessments and penetration testing to identify potential weaknesses.

Evidence notes

The CVE-2026-53182 vulnerability has been identified in the Linux kernel, specifically in the nl80211 component. The vulnerability allows for an out-of-bounds write due to improper validation of EMA RNR lists. The fix involves rejecting oversized EMA RNR lists to prevent potential buffer overflows. The CVSS score for this vulnerability is 7.8, indicating a HIGH severity level.

Official resources