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PatchSiren cyber security CVE debrief

CVE-2026-64095 Linux CVE debrief

A vulnerability was found in the Linux kernel's batman-adv module. The bla.num_requests counter was not being updated atomically, allowing for a double decrement error. This could lead to incorrect request tracking and potential issues with the batman-adv module. The issue was addressed by ensuring atomic updates to the counter and related state variables. Linux kernel users and administrators should be aware of this vulnerability and take necessary precautions. Affected product deployments should be identified and owners assigned for follow-up.

Vendor
Linux
Product
Unknown
CVSS
Unknown
CISA KEV
Not listed in stored evidence
Original CVE published
2026-07-19
Original CVE updated
2026-07-19
Advisory published
2026-07-19
Advisory updated
2026-07-19

Who should care

Linux kernel users and administrators, network security teams, and operators of affected systems should be aware of this vulnerability and take necessary precautions to mitigate its impact. Affected operators, platforms, and security teams should review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.

Technical summary

The batman-adv module in the Linux kernel did not properly synchronize access to the bla.num_requests counter, leading to a potential double decrement error. This issue was addressed by ensuring atomic updates to the counter and related state variables. The fix involves modifying the request_sent state and bla.num_requests counter atomically to prevent TOCTOU errors. Linux kernel users and administrators should be aware of this vulnerability and take necessary precautions to mitigate its impact.

Defensive priority

Medium

Recommended defensive actions

  • Apply kernel updates
  • Monitor system logs
  • Implement network segmentation
  • Review compensating controls for exposed systems
  • Check relevant monitoring, detection, and logs for exposed assets
  • Track exceptions and retest remediated assets
  • Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance

Evidence notes

Evidence is limited to NVD and CVE.org records. Further analysis is needed to fully understand the impact of this vulnerability. Linux kernel users should verify their deployments and check for official vendor guidance. The CVE record was published on 2026-07-19T16:17:50.470Z and has not been modified since then. No additional information is available from other sources. Defenders should verify affected product deployments and review system logs for potential exploitation.

Official resources

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-07-19T16:17:50.470Z and has not been modified since then.