Vulnerability in Linux kernel (CVE-2026-52961)
Summary
Vulnerability in Linux kernel (CVE-2026-52961). 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:
ceph: fix BUG_ON in __ceph_build_xattrs_blob() due to stale blob size
The generic/642 test-case can reproduce the kernel crash:
[40243.605254] ------------[ cut here ]------------
[40243.605956] kernel BUG at fs/ceph/xattr.c:918!
[40243.607142] Oops: invalid opcode: 0000 [#1] SMP PTI
[40243.608067] CPU: 7 UID: 0 PID: 498762 Comm: kworker/7:1 Not tainted 7.0.0-rc7+ #3 PREEMPT(full)
[40243.609700] Hardware name: QEMU Ubuntu 25.10 PC v2 (i440FX + PIIX, + 10.1 machine, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[40243.611820] Workqueue: ceph-msgr ceph_con_workfn
[40243.612715] RIP: 0010:__ceph_build_xattrs_blob+0x1b8/0x1e0
[40243.613731] Code: 0f 84 82 fe ff ff e9 cf 8e 56 ff 48 8d 65 e8 31 c0 5b 41 5c 41 5d 5d 31 d2 31 c9 31 f6 31 ff 45 31 c0 45 31 c9 c3 cc cc cc cc <0f> 0b 4c 8b 62 08 41 8b 85 24 07 00 00 49 83 c4 04 41 89 44 24 fc
[40243.616888] RSP: 0018:ffffcc80c4d4b688 EFLAGS: 00010287
[40243.617773] RAX: 0000000000010026 RBX: 0000000000000001 RCX: 0000000000000000
[40243.618928] RDX: ffff8a773798dee0 RSI: 0000000000000000 RDI: 0000000000000000
[40243.620158] RBP: ffffcc80c4d4b6a0 R08: 0000000000000000 R09: 0000000000000000
[40243.621573] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8a75f3b58000
[40243.622907] R13: ffff8a75f3b58000 R14: 0000000000000080 R15: 000000000000bffd
[40243.624054] FS: 0000000000000000(0000) GS:ffff8a787d1b4000(0000) knlGS:0000000000000000
[40243.625331] CS: 0010 DS:…
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-2026-52961 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-2026-52961" on the vendor's site.
CVE-2026-52961 (Linux kernel) — CWE-617 / 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 (CWE-617) 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。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- BellSoft Alpaquita BELL-CVE-2026-52961 linux-lts
- Debian DEBIAN-CVE-2026-52961 linux
- Ubuntu UBUNTU-CVE-2026-52961 linux-hwe-edge
References
- web nvd.nist.gov
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web github.com
- web git.kernel.org