Vulnerability in Linux kernel (CVE-2026-89486)
Summary
Vulnerability in Linux kernel (CVE-2026-89486). 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:
ipmi: Fix use-after-free of cmd_rcvr in _ipmi_destroy_user()
Commit 9e91f8a6c868 ("ipmi:msghandler: Remove srcu for the
ipmi_interfaces list") dropped the synchronize_rcu() between unlinking
the command receivers from intf->cmd_rcvrs and freeing them, updating
only the comment that explains why the barrier is needed.
The cmd_rcvrs list is still traversed under plain RCU: find_cmd_rcvr()
walks it inside rcu_read_lock(), and handle_ipmb_get_msg_cmd() borrows
rcvr->user from that lookup within the same read-side section. Without
the grace period, _ipmi_destroy_user() can kfree() a cmd_rcvr while a
reader still holds a pointer to it, causing a use-after-free.
The rework only made srcu unnecessary for the interfaces list; the
cmd_rcvrs list still relies on plain RCU. Restore the synchronize_rcu()
before freeing the receivers.
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-2026-89486 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-2026-89486" on the vendor's site.
CVE-2026-89486 (Linux kernel) — CVSS v3 7.8
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: 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
- Ubuntu UBUNTU-CVE-2026-89486 linux-hwe-edge
References
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web nvd.nist.gov
- web github.com