Vulnerability in Linux kernel (CVE-2026-90092)
Summary
Vulnerability in Linux kernel (CVE-2026-90092). 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:
Bluetooth: L2CAP: reject accept queue add unless BT_LISTEN
New sk should not be added to parent socket accept queue after last
l2cap_sock_cleanup_listen() has run in l2cap_sock_teardown_cb() and
state set to BT_CLOSED, as that can result to UAF on dereferencing the
dangling parent reference.
l2cap_sock_new_connection_cb() may race with parent l2cap_chan teardown,
due to chan->state accessed without consistent locking:
[Task 1] [Task 2]
l2cap_sock_release(parent) l2cap_connect
l2cap_sock_shutdown pchan = l2cap_global_chan_by_psm
l2cap_chan_lock(pchan)
l2cap_chan_close
l2cap_sock_teardown_cb
pchan->state = BT_CLOSED
l2cap_chan_unlock(pchan) ------> l2cap_chan_lock(pchan)
l2cap_new_connection
l2cap_sock_new_connection_cb
l2cap_chan_lock(pchan) <-------- l2cap_chan_unlock(pchan)
l2cap_sock_kill(parent) /* bt_sk(sk)->parent dangling */
Fix by adding check for sk_state == BT_LISTEN after acquiring sk lock in
l2cap_sock_new_connection_cb(). Add lock_sock() around sk_state writes
where missing, to avoid data races.
Although the data races on pchan->state should be fixed too, this
defensive sk_state check probably makes sense in any case.
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-2026-90092 has been found in Linux kernel.
Successful exploitation can lead to full system takeover. CVSS score: 8.0/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2026-90092" on the vendor's site.
CVE-2026-90092 (Linux kernel) — CVSS v3 8.0
Attack vector: adjacent-network / 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 8.0/10). 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。
References
- 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 nvd.nist.gov
- web github.com