Vulnerability in Linux kernel (CVE-2026-90205)
Summary
Vulnerability in Linux kernel (CVE-2026-90205). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
In the Linux kernel, the following vulnerability has been resolved:
ocfs2: validate orphan slot during inode read
Patch series "ocfs2: validate active orphan slots during inode read".
OCFS2 trusts active ordinary and append-DIO orphan slots read from dinodes.
A corrupted slot can therefore index osb_orphan_wipes or the slot-local
system-inode cache outside their allocations before the corruption is
reported.
Patch 1 validates the ordinary orphan slot used by inode wipe processing.
Patch 2 validates the append-DIO orphan slot used by DIO completion and
orphan recovery. Both checks reject corrupt metadata at the existing inode
validation boundary.
This patch (of 2):
[BUG]
A corrupted dinode with OCFS2_ORPHANED_FL can carry an
i_orphaned_slot outside the mounted filesystem slot range.
ocfs2_wipe_inode() uses it to index osb_orphan_wipes before looking
up the orphan directory, causing an out-of-bounds memory access.
BUG: KASAN: slab-use-after-free in ocfs2_get_system_file_inode+0x780/0x820 fs/ocfs2/sysfile.c:102
Read of size 8 at addr ffff88800b767c00 by task kworker/u8:3/85
Call Trace:
...
ocfs2_get_system_file_inode+0x780/0x820 fs/ocfs2/sysfile.c:102
ocfs2_wipe_inode+0x292/0xf70 fs/ocfs2/inode.c:840
ocfs2_delete_inode fs/ocfs2/inode.c:1155 [inline]
ocfs2_evict_inode+0x6c9/0x1170 fs/ocfs2/inode.c:1295
evict+0x38e/0x8f0 fs/inode.c:810
iput_final fs/inode.c:1914 [inline]
iput fs/inode.c:1966 [inline]
iput+0x55b/0x8b0 fs/inode.c:1926
ocfs2_recover_orphans+0x610/0x…
Source: NIST National Vulnerability Database 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-2026-90205 has been found in Linux kernel.
Successful exploitation can lead to full system takeover. CVSS score: 7.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2026-90205" on the vendor's site.
CVE-2026-90205 (Linux kernel) — CVSS v3 7.8
Attack vector: local / unauthenticated
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: High (CVSS 7.8/10). Successful exploitation can lead to full system takeover.
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
- Debian DEBIAN-CVE-2026-90205 linux
- Ubuntu UBUNTU-CVE-2026-90205 linux
References
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web nvd.nist.gov
- web github.com