CVE-2025-38349

Unspecified local impact via premature eventpoll refcount decrement

Published Jul 18, 2025 · Updated Aug 5, 2026

Use-after-free in Linux kernel eventpoll in affected Linux versions allows local users to cause unspecified impact through an epoll race. The eventpoll teardown path decrements an epoll object's reference count before mutex_unlock finishes accessing ep->mtx, allowing another thread to free the object during unlock. Triggering the flaw requires local low-privileged access and a next-to-last reference race; the CNA does not identify a specific post-use consequence beyond the use-after-free.

CVSS severity7.8
High
EPSS probability0.16%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in Linux kernel eventpoll in affected Linux versions allows local users to cause unspecified impact through an epoll race. The eventpoll teardown path decrements an epoll object's reference count before mutex_unlock finishes accessing ep->mtx, allowing another thread to free the object during unlock. Triggering the flaw requires local low-privileged access and a next-to-last reference race; the CNA does not identify a specific post-use consequence beyond the use-after-free.

The record

CVE
CVE-2025-38349
Published
Jul 18, 2025
Updated
Aug 5, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-416
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 18, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 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=5.15.209 <5.16
  2. Affected versionversion=58c9b016e12855286370dfb704c08498edbc857a <521e9ff0b67c66a17d6f9593dfccafaa984aae4c
  3. Affected versionversion=58c9b016e12855286370dfb704c08498edbc857a <605c18698ecfa99165f36b7f59d3ed503e169814
  4. Affected versionversion=58c9b016e12855286370dfb704c08498edbc857a <6dee745bd0aec9d399df674256e7b1ecdb615444
  5. Affected versionversion=58c9b016e12855286370dfb704c08498edbc857a <8c2e52ebbe885c7eeaabd3b7ddcdc1246fc400d2
  6. Affected versionversion=6.1.175 <6.1.178
  7. Affected versionversion=6.4
  8. Affected versionversion=a1f93804449d13f97dabd4b996817de4bf1ed67a <b0821ec902d39062356cb644c16e17a705d1c9f5
  9. Affected versionversion=f2451def095c1743adcfcb0cb5dadc86034e162a

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=5.15.209 <5.16; version=58c9b016e12855286370dfb704c08498edbc857a <521e9ff0b67c66a17d6f9593dfccafaa984aae4c; version=58c9b016e12855286370dfb704c08498edbc857a <605c18698ecfa99165f36b7f59d3ed503e169814; version=58c9b016e12855286370dfb704c08498edbc857a <6dee745bd0aec9d399df674256e7b1ecdb615444; version=58c9b016e12855286370dfb704c08498edbc857a <8c2e52ebbe885c7eeaabd3b7ddcdc1246fc400d2; version=6.1.175 <6.1.178; version=6.4; version=a1f93804449d13f97dabd4b996817de4bf1ed67a <b0821ec902d39062356cb644c16e17a705d1c9f5; version=f2451def095c1743adcfcb0cb5dadc86034e162a

Published CVSS scores

7.8Linux CNACVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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-416Use After Free

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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