CVE-2026-93203 Linux CVE debrief

Who should care

Linux kernel developers and maintainers, network administrators, and security teams responsible for Linux kernel-based systems should review and verify system configurations to prevent potential issues with CRC corruption and claim validation. They should also monitor for potential issues and review compensating controls for exposed systems.

Why it matters

A vulnerability in the Linux kernel's batman-adv module could allow an attacker to corrupt CRC values, potentially leading to issues with claim validation and backbone updates. Linux kernel developers and maintainers, network administrators, and security teams should review and verify system configurations to prevent potential issues.

• Verification of claim validation processes to prevent potential issues with CRC corruption
• Review and update of Linux kernel configurations to ensure secure batman-adv module operation
• Monitoring of system logs for potential CRC corruption issues

Technical summary

The batman-adv module in the Linux kernel has a vulnerability that could lead to CRC corruption due to parallel claim additions. This issue arises from the handling of claims and modifications to the backbone of claims for CLAIM frames from remote backbones and local packets. The vulnerability can cause CRC corruption, affecting the validation and updates of claims in the batman-adv module. The issue has been resolved in the Linux kernel, and the batman-adv module has been updated to address the CRC corruption issue.

Defensive priority

Medium

Recommended defensive actions

• Review Linux kernel updates and patches for the batman-adv module
• Verify system configurations and claim validation processes
• Monitor for potential issues with CRC corruption
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, but do not specify versions, exploitation, impact, or remediation. Further verification is required from official Linux kernel sources. The vulnerability has been resolved in the Linux kernel, and the batman-adv module has been updated to address the CRC corruption issue. However, the exact versions affected and the specific remediation steps are not provided in the CVE record or NVD entry.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.