Vulnerability in Linux kernel (CVE-2025-71304)
Summary
Vulnerability in Linux kernel (CVE-2025-71304). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
In the Linux kernel, the following vulnerability has been resolved:
smack: /smack/doi: accept previously used values
Writing to /smack/doi a value that has ever been
written there in the past disables networking for
non-ambient labels.
E.g.
# cat /smack/doi
3
# netlabelctl -p cipso list
Configured CIPSO mappings (1)
DOI value : 3
mapping type : PASS_THROUGH
# netlabelctl -p map list
Configured NetLabel domain mappings (3)
domain: "_" (IPv4)
protocol: UNLABELED
domain: DEFAULT (IPv4)
protocol: CIPSO, DOI = 3
domain: DEFAULT (IPv6)
protocol: UNLABELED
# cat /smack/ambient
_
# cat /proc/$$/attr/smack/current
_
# ping -c1 10.1.95.12
64 bytes from 10.1.95.12: icmp_seq=1 ttl=64 time=0.964 ms
# echo foo >/proc/$$/attr/smack/current
# ping -c1 10.1.95.12
64 bytes from 10.1.95.12: icmp_seq=1 ttl=64 time=0.956 ms
unknown option 86
# echo 4 >/smack/doi
# echo 3 >/smack/doi
!> [ 214.050395] smk_cipso_doi:691 cipso add rc = -17
# echo 3 >/smack/doi
!> [ 249.402261] smk_cipso_doi:678 remove rc = -2
!> [ 249.402261] smk_cipso_doi:691 cipso add rc = -17
# ping -c1 10.1.95.12
!!> ping: 10.1.95.12: Address family for hostname not supported
# echo _ >/proc/$$/attr/smack/current
# ping -c1 10.1.95.12
64 bytes from 10.1.95.12: icmp_seq=1 ttl=64 time=0.617 ms
This happens because Smack keeps decommissioned DOIs,
fails to re-add them, and conseque…
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2025-71304 has been found in Linux kernel.
Risk of unauthorized operations or information disclosure. CVSS score: 5.5/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2025-71304" on the vendor's site.
CVE-2025-71304 (Linux kernel) — CVSS v3 5.5
Attack vector: local / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (unclassified) exists in Linux kernel.
Check the vendor advisory for the affected versions of Linux kernel.
Severity: Medium (CVSS 5.5/10). Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Linux kernel を使っているサービスとバージョンを洗い出す。
-
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- BellSoft Alpaquita BELL-CVE-2025-71304 linux-lts Fixed in: 6.1.167-r0
- Debian DEBIAN-CVE-2025-71304 linux Fixed in: 5.10.257-1
- Ubuntu UBUNTU-CVE-2025-71304 linux
References
- advisory nvd.nist.gov
- advisory github.com
- package git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web github.com