Unknown

CVE-2026-89752 — mm: memcg: stop reclaim when a limit update is superseded

In the Linux kernel, the following vulnerability has been resolved: mm: memcg: stop reclaim when a limit update is superseded kernfs serializes file operations only per open file, so separate open files can update the same memory.high or memory.max file concurrently.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.

Published Sep 11, 2026 · Updated Oct 19, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: Linux

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.2% (30-day exploitation probability)+1

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.18%

ahead of 7% of scored CVEs · Oct 23, 2026

Affects

Linux

CVSS base

—

Score not published yet.

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Linux	Linux	≥ b6e6edcfa40561e9c8abe5eecf1c96f8e5fd9c6f and < ebf762a393630d1582645be3f0fc22a674eb9122≥ b6e6edcfa40561e9c8abe5eecf1c96f8e5fd9c6f and < 4ea0617b9e46d26c0a3e5af00308ea1931cc545d≥ b6e6edcfa40561e9c8abe5eecf1c96f8e5fd9c6f and < 5c6f87d33733d96fba66ea4e78cd8b24b4d60a49≥ b6e6edcfa40561e9c8abe5eecf1c96f8e5fd9c6f and < 8bf21ad3657305e28deafd9ef16a121407496bc3≥ b6e6edcfa40561e9c8abe5eecf1c96f8e5fd9c6f and < 39ec1e4183a718f448b2e9de681dcbdda18fce42≥ b6e6edcfa40561e9c8abe5eecf1c96f8e5fd9c6f and < 95d87030cae7764805aa7c621c52871139297cb0≥ b6e6edcfa40561e9c8abe5eecf1c96f8e5fd9c6f and < aab391074de96ed601eeca32daef9a8507d436d9≥ b6e6edcfa40561e9c8abe5eecf1c96f8e5fd9c6f and < 9477820c63cbf4d97114238f3d1ff10dfd6bee3f and 5 more version 0ccab5b139971a2a3f48df24d1ee8be2dbf84042version 97729c37439040ec07807f0dbb71ea60ccbafd27≥ 4.4.7 and < 4.5≥ 4.5.1 and < 4.6version 4.6	Vulnerable	CVE Program (cve.org) e CISA ADP

EPSS over time FIRST

Oct 15, 2026 → Oct 23, 2026 · 8 reading(s) · max 0.18%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Not enough vector or weakness data: use the affected application’s logs as a starting point.

application logs

Timeline

What happened to this CVE, newest first.

2026
Record published
Oct 15, 2026
Affected products added · linux/linux
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
Source status changed · → Received
Oct 15, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 15, 2026 · NIST National Vulnerability Database
CVE published
Sep 11, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

1× References added · Oct 19, 2026 – Oct 19, 2026
1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

10 on the record

git.kernel.org/stable/c/4ea0617b9e46d26c0a3e5af00308ea1931cc545d
NIST National Vulnerability Database
git.kernel.org/stable/c/ebf762a393630d1582645be3f0fc22a674eb9122
NIST National Vulnerability Database
github.com/advisories/GHSA-8w7m-rmxj-xxh8
GitHub Security Advisories
git.kernel.org/stable/c/5c6f87d33733d96fba66ea4e78cd8b24b4d60a49
NIST National Vulnerability Database
git.kernel.org/stable/c/9477820c63cbf4d97114238f3d1ff10dfd6bee3f
NIST National Vulnerability Database
git.kernel.org/stable/c/aab391074de96ed601eeca32daef9a8507d436d9
NIST National Vulnerability Database
git.kernel.org/stable/c/8bf21ad3657305e28deafd9ef16a121407496bc3
NIST National Vulnerability Database
nvd.nist.gov/vuln/detail/CVE-2026-89752
GitHub Security Advisories
git.kernel.org/stable/c/95d87030cae7764805aa7c621c52871139297cb0
NIST National Vulnerability Database
git.kernel.org/stable/c/39ec1e4183a718f448b2e9de681dcbdda18fce42
NIST National Vulnerability Database

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

Unknown CVE-2026-99086 dm-integrity: validate the superblock on resume 1d
Unknown CVE-2026-99087 dm-integrity: fix NULL pointer dereference when the 'R' flag is used 1d
Unknown CVE-2026-99080 fs: Free any excess xarray nodes in clear_inode() 1d
Unknown CVE-2026-99084 readdir: take no inode lock on an immutable directory 1d
Unknown CVE-2026-99085 sched_ext: Fix CPU hotplug hang when a dying CPU's tasks sit in the BPF scheduler 1d
Critical CVE-2026-99079 net/mlx5e: Prevent stale XSK buffer release on refill retry 1d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No CVSS score published by NVD, the CNA, CISA or GitHub so far.
No fixed version, patch or mitigation documented.
No CISA SSVC assessment.
No CWE classification.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-89752 is "mm: memcg: stop reclaim when a limit update is superseded", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.18% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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