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CVE-2026-53153 Linux CVE debrief

CVE-2026-53153 is a vulnerability in the Linux kernel's memory management subsystem. The vulnerability arises from the memcg_reparent_list_lrus function, which clears the dying memcg's xarray entry before reparenting its per-node lists into the parent. This creates a window where a concurrent list_lru_del operation can see the xarray entry as NULL, leading to a use-after-free condition. An attacker with local access can exploit this vulnerability to cause a denial-of-service or potentially execute arbitrary code. The vulnerability has been resolved by reversing the order of operations in memcg_reparent_list_lrus. The Linux kernel community has addressed this issue, and users are advised to update to the patched version.

Vendor
Linux
Product
Unknown
CVSS
HIGH 7.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-25
Original CVE updated
2026-06-28
Advisory published
2026-06-25
Advisory updated
2026-06-28

Who should care

System administrators and security teams responsible for Linux kernel-based systems should be aware of this vulnerability. Given its HIGH CVSS score of 7.8, organizations using affected kernel versions should prioritize patching. This vulnerability can be exploited locally, making it a significant concern for multi-user systems or those with untrusted local access.

Technical summary

The vulnerability is located in the mm/list_lru.c file of the Linux kernel. The memcg_reparent_list_lrus function was not properly synchronizing access to the dying memcg's xarray entry and its per-node lists. By clearing the xarray entry before reparenting the lists, it created a race condition where concurrent list_lru_del operations could lead to use-after-free errors. The fix involves reparenting the per-node lists and marking the child's list_lru dead before clearing the xarray entry. This ensures that any concurrent operations will either see the still-set xarray entry and synchronize with the drain or see LONG_MIN and walk to the parent where the items now reside.

Defensive priority

Apply the official patch from the Linux kernel community as soon as possible. Review system logs for signs of exploitation attempts, and monitor system stability after applying the patch.

Recommended defensive actions

  • Apply the official Linux kernel patch to address the vulnerability.
  • Review system logs for suspicious activity related to the affected subsystem.
  • Monitor system stability and performance after applying the patch.
  • Inventory Linux kernel versions in use across the organization to ensure all affected systems are identified and patched.
  • Consider implementing additional monitoring for local access and privilege escalation attempts.

Evidence notes

The CVE-2026-53153 vulnerability was made public on 2026-06-25 with a CVSS score of 7.8. The Linux kernel community has provided patches to address this issue. The vulnerability allows local attackers to potentially escalate privileges or cause a denial-of-service. Evidence from the Linux kernel mailing lists and Git repositories confirms the vulnerability and its fix.

Official resources

This article is AI-assisted and based on the supplied source corpus.