Vulnerability in Linux kernel (CVE-2026-68405)
Summary
Vulnerability in Linux kernel (CVE-2026-68405). 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:
wifi: mac80211: free AP_VLAN bc_buf SKBs outside IRQ lock
ieee80211_do_stop() removes AP_VLAN packets from the parent AP
ps->bc_buf while holding ps->bc_buf.lock with IRQs disabled. It then
calls ieee80211_free_txskb() before dropping the lock.
ieee80211_free_txskb() is not just a passive SKB release. For SKBs with
TX status state it can report a dropped frame through cfg80211/nl80211,
and that path can reach netlink tap transmit. This is the same reason
the pending queue cleanup in ieee80211_do_stop() already unlinks SKBs
under the queue lock and frees them after IRQ state is restored.
The buggy scenario involves two paths, with each column showing the
order within that path:
AP_VLAN management TX: AP_VLAN stop:
- attach ACK-status state 1. clear the running state
- queue a multicast SKB on 2. take ps->bc_buf.lock with IRQs
parent ps->bc_buf disabled
3. unlink the AP_VLAN SKB
4. call ieee80211_free_txskb()
Unlink matching AP_VLAN SKBs from ps->bc_buf under the existing lock,
but move them to a local free queue. Drop the lock and restore IRQ state
before calling ieee80211_free_txskb().
WARNING: kernel/softirq.c:430 at __local_bh_enable_ip
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-2026-68405 has been found in Linux kernel.
Risk of unauthorized operations or information disclosure.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2026-68405" on the vendor's site.
CVE-2026-68405 (Linux kernel)
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: ?. 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
- Debian DEBIAN-CVE-2026-68405 linux Fixed in: 6.1.187-1
- Ubuntu UBUNTU-CVE-2026-68405 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 github.com
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org