CVE-2026-31567

Kernel warning via unmatched GFP-mask restore

Published Apr 24, 2026 · Updated Apr 24, 2026

Reachable assertion in Linux Kernel 6.18 allows local users to trigger a kernel warning through defensive hibernation operations. pm_restore_gfp_mask() applies WARN_ON() when saved_gfp_count is zero, although several uswsusp paths legitimately call the restore defensively. Local access to those hibernation operations is required; panic_on_warn converts the warning into a kernel panic, while its disabled state limits the effect to diagnostic noise.

CVSS severity5.5
Medium
EPSS probability0.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reachable assertion in Linux Kernel 6.18 allows local users to trigger a kernel warning through defensive hibernation operations. pm_restore_gfp_mask() applies WARN_ON() when saved_gfp_count is zero, although several uswsusp paths legitimately call the restore defensively. Local access to those hibernation operations is required; panic_on_warn converts the warning into a kernel panic, while its disabled state limits the effect to diagnostic noise.

The record

CVE
CVE-2026-31567
Published
Apr 24, 2026
Updated
Apr 24, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
CWE-617, T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 24, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 24, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=35e4a69b2003f20a69e7d19ae96ab1eef1aa8e8d <3025ca5daa9d682b629c0c958b538e41deeb559d
  2. Affected versionversion=35e4a69b2003f20a69e7d19ae96ab1eef1aa8e8d <a8d51efb5929ae308895455a3e496b5eca2cd143
  3. Affected versionversion=35e4a69b2003f20a69e7d19ae96ab1eef1aa8e8d <f19d1323aa3dd7ead469aef47d9085f8939565d9
  4. Affected versionversion=4ddf7293928cb619077724b7d828734da8181e6c
  5. Affected versionversion=6.18

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=35e4a69b2003f20a69e7d19ae96ab1eef1aa8e8d <3025ca5daa9d682b629c0c958b538e41deeb559d; version=35e4a69b2003f20a69e7d19ae96ab1eef1aa8e8d <a8d51efb5929ae308895455a3e496b5eca2cd143; version=35e4a69b2003f20a69e7d19ae96ab1eef1aa8e8d <f19d1323aa3dd7ead469aef47d9085f8939565d9; version=4ddf7293928cb619077724b7d828734da8181e6c; version=6.18

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-617Reachable Assertion
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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