0.0
NA
CVE-2026-89752
mm: memcg: stop reclaim when a limit update is superseded
Description

In the Linux kernel, the following vulnerability has been resolved: mm: memcg: stop reclaim when a limit update is superseded kernfs serializes file operations only per open file, so separate open files can update the same memory.high or memory.max file concurrently. Both handlers store the new limit before synchronous reclaim, but continue to use the writer's local target in the reclaim loop. If another writer raises or removes the limit, the first writer can continue reclaiming toward a stale target. For memory.max, this can leave the writer looping indefinitely once reclaim retries are exhausted. The OOM path sees sufficient margin under the current limit and returns true without killing, while the writer still compares usage against its stale target and records another OOM event. Check the current limit at the start of each reclaim iteration and stop if it no longer matches the writer's target. Reproducer: Populate a cgroup with anonymous memory and disable swapping. Lower memory.max from one open file, then restore it to "max" through another open file after the new limit becomes visible. Without the patch, the first writer remains blocked and repeatedly increments the OOM event counter. With the patch, it returns normally. This was not motivated by a reported production workload. We found it through automated randomized testing for our cgroup observability work and reduced it to the reproducer above.

INFO

Published Date :

Sept. 11, 2026, 8:20 p.m.

Last Modified :

Sept. 11, 2026, 8:20 p.m.

Remotely Exploit :

No

Source :

416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products

The following products are affected by CVE-2026-89752 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

Solution
Update the Linux kernel to address a race condition in memory cgroup limit handling.
  • Update the Linux kernel to the latest version.
  • Apply the specific patch for the memcg reclaim issue.
  • Verify reclaim logic against current limits.
  • Ensure limit updates are properly synchronized.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-89752 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-89752 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-89752 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-89752 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67

    Sep. 11, 2026

    Action Type Old Value New Value
    Added Description In the Linux kernel, the following vulnerability has been resolved: mm: memcg: stop reclaim when a limit update is superseded kernfs serializes file operations only per open file, so separate open files can update the same memory.high or memory.max file concurrently. Both handlers store the new limit before synchronous reclaim, but continue to use the writer's local target in the reclaim loop. If another writer raises or removes the limit, the first writer can continue reclaiming toward a stale target. For memory.max, this can leave the writer looping indefinitely once reclaim retries are exhausted. The OOM path sees sufficient margin under the current limit and returns true without killing, while the writer still compares usage against its stale target and records another OOM event. Check the current limit at the start of each reclaim iteration and stop if it no longer matches the writer's target. Reproducer: Populate a cgroup with anonymous memory and disable swapping. Lower memory.max from one open file, then restore it to "max" through another open file after the new limit becomes visible. Without the patch, the first writer remains blocked and repeatedly increments the OOM event counter. With the patch, it returns normally. This was not motivated by a reported production workload. We found it through automated randomized testing for our cgroup observability work and reduced it to the reproducer above.
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/89xxx/CVE-2026-89752.json">CVE-2026-89752</a>
    Added Reference https://git.kernel.org/stable/c/39ec1e4183a718f448b2e9de681dcbdda18fce42
    Added Reference https://git.kernel.org/stable/c/9477820c63cbf4d97114238f3d1ff10dfd6bee3f
    Added Reference https://git.kernel.org/stable/c/95d87030cae7764805aa7c621c52871139297cb0
    Added Reference https://git.kernel.org/stable/c/aab391074de96ed601eeca32daef9a8507d436d9
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.