CVE-2025-38588

Local kernel hang via RCU sibling-list race

Published Aug 19, 2025 · Updated May 23, 2026

Infinite-loop flaw in the Linux IPv6 routing code allows local users to hang kernel route-message generation through a route-update race. Concurrent fib6_del_route() or fib6_add_rt2node() calls use list_del_rcu(), so rt6_nlmsg_size() can lose the sibling-list head and loop forever. Low-privileged local access and concurrent route mutation are required; the documented impact is availability loss without data disclosure or modification.

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

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Infinite-loop flaw in the Linux IPv6 routing code allows local users to hang kernel route-message generation through a route-update race. Concurrent fib6_del_route() or fib6_add_rt2node() calls use list_del_rcu(), so rt6_nlmsg_size() can lose the sibling-list head and loop forever. Low-privileged local access and concurrent route mutation are required; the documented impact is availability loss without data disclosure or modification.

The record

CVE
CVE-2025-38588
Published
Aug 19, 2025
Updated
May 23, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
T1499
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 19, 2025CVE publishedPublication date reported by the CVE source.
  2. May 23, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=11edcd026012ac18acee0f1514db3ed1b160fc6f
  2. Affected versionversion=34a949e7a0869dfa31a40416d2a56973fae1807b <cd8d8bbd9ced4cc5d06d858f67d4aa87745e8f38
  3. Affected versionversion=52da02521ede55fb86546c3fffd9377b3261b91f <e1b7932af47f92432be8303d2439d1bf77b0be23
  4. Affected versionversion=6.11.11 <6.12
  5. Affected versionversion=6.1.128 <6.1.148
  6. Affected versionversion=6.12.2 <6.12.42
  7. Affected versionversion=6.13
  8. Affected versionversion=6.6.75 <6.6.102
  9. Affected versionversion=d0ec61c9f3583b76aebdbb271f5c0d3fcccd48b2 <6d345136c9b875f065d226908a29c25cdf9343f8
  10. Affected versionversion=d9ccb18f83ea2bb654289b6ecf014fd267cc988b <3c13db3e47e170bab19e574404e7b6be45ea873d
  11. Affected versionversion=d9ccb18f83ea2bb654289b6ecf014fd267cc988b <46aeb66e9e54ed0d56c18615e1c3dbd502b327ab
  12. Affected versionversion=d9ccb18f83ea2bb654289b6ecf014fd267cc988b <54e6fe9dd3b0e7c481c2228782c9494d653546da

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=11edcd026012ac18acee0f1514db3ed1b160fc6f; version=34a949e7a0869dfa31a40416d2a56973fae1807b <cd8d8bbd9ced4cc5d06d858f67d4aa87745e8f38; version=52da02521ede55fb86546c3fffd9377b3261b91f <e1b7932af47f92432be8303d2439d1bf77b0be23; version=6.11.11 <6.12; version=6.1.128 <6.1.148; version=6.12.2 <6.12.42; version=6.13; version=6.6.75 <6.6.102; version=d0ec61c9f3583b76aebdbb271f5c0d3fcccd48b2 <6d345136c9b875f065d226908a29c25cdf9343f8; version=d9ccb18f83ea2bb654289b6ecf014fd267cc988b <3c13db3e47e170bab19e574404e7b6be45ea873d; version=d9ccb18f83ea2bb654289b6ecf014fd267cc988b <46aeb66e9e54ed0d56c18615e1c3dbd502b327ab; version=d9ccb18f83ea2bb654289b6ecf014fd267cc988b <54e6fe9dd3b0e7c481c2228782c9494d653546da

Published CVSS scores

5.5OracleCVSS: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.

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

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

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo