CVE-2026-53247 Linux CVE debrief

Who should care

This vulnerability affects Linux kernel users, particularly those using the mtk_eth_soc component. System administrators and security teams should be aware of this vulnerability and take necessary steps to mitigate it. Linux distribution maintainers and kernel developers should also be aware of this vulnerability and apply the necessary patches.

Technical summary

The vulnerability is caused by a use-after-free error in the metadata dst teardown process. The mtk_free_dev() function calls metadata_dst_free(), which frees the metadata_dst with kfree() immediately, bypassing the RCU grace period. This can cause a use-after-free error if any skb still holds a noref pointer to the dst when the driver tears it down. The fix is to replace metadata_dst_free() with dst_release(), which properly goes through the refcount path and ensures that all RCU readers have completed before the memory is freed.

Defensive priority

High priority should be given to patching this vulnerability, as it has a high CVSS score and can be exploited remotely. Linux kernel users should apply the necessary patches as soon as possible.

Recommended defensive actions

• Apply the patch from the Linux kernel repository that replaces metadata_dst_free() with dst_release().
• Review and update Linux kernel configurations to ensure that the mtk_eth_soc component is properly configured and secured.
• Monitor system logs for potential exploitation attempts.
• Consider implementing additional security controls, such as network segmentation and access controls, to limit the attack surface.
• Keep Linux kernel and distribution up to date with the latest security patches.

Evidence notes

The CVE record and NVD detail provide information on the vulnerability, including its description, CVSS score, and references. The Linux kernel repository provides the patch that fixes the vulnerability.

Official resources