CVE-2026-68429: Linux kernel · drm/dp_mst: Handle torn-down topology gracefully in drm_dp_mst_topology_queue_probe()
Affects Linux kernelSource CVE Database V5
Not known to be exploited · fixed in b1d05cc61dfa6c4bd5e67855bec6a03e955f512d : update Linux kernel when convenient.
Data as of 6 Nov 2026, 17:04 UTC
Rated by Threat Radar · No CVSS score from NVD or the CNA
Thin evidence
One scorer or none- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Limited control over the software or limited information exposure
CISA SSVC assessment, 2026-11-06.
- Patch
- Available – fixed in b1d05cc61dfa6c4bd5e67855bec6a03e955f512d, afdff9103818656627920c21822e48a6dae2906f, 613059875958e7b217b250ed14c3b189f9488421 +3
Exploitation evidence
Disclosed: evidence found.
CVE published 12 Aug 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 6 Nov 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
|
| LinuxLinux | Affected
| Fixed in– |
Description
In the Linux kernel, the following vulnerability has been resolved: drm/dp_mst: Handle torn-down topology gracefully in drm_dp_mst_topology_queue_probe() A hotplug or link-loss event can tear down the MST topology (setting mgr->mst_state = false and mgr->mst_primary = NULL) concurrently with a caller invoking drm_dp_mst_topology_queue_probe(). Since the check is already performed under mgr->lock, the condition is not a programming error but a valid race -- the topology was valid when the caller decided to call this function, but was torn down before the lock was acquired. Replace the drm_WARN_ON() with a graceful early return. This eliminates spurious kernel warnings and the resulting compositor crashes observed when connecting/disconnecting DP MST monitors, while keeping the correct behavior of doing nothing when MST is not active. A drm_dbg_mst() trace is added so the skipped probe remains observable under MST debug logging. The existing WARN_ON(mgr->mst_primary) in drm_dp_mst_topology_mgr_set_mst() already catches the case where the topology is initialized twice, so no diagnostic coverage is lost.
References
- git.kernel.org/stable/c/b1d05cc61dfa6c4bd5e67855bec6a03e955f512d (opens in a new tab)
- git.kernel.org/stable/c/4ed6d08c4a59ee6a8cb806347f6d9873de5d229e (opens in a new tab)
- git.kernel.org/stable/c/8c6d84a54823cd839e6ce22af559925f1320c310 (opens in a new tab)
- git.kernel.org/stable/c/afdff9103818656627920c21822e48a6dae2906f (opens in a new tab)
- git.kernel.org/stable/c/613059875958e7b217b250ed14c3b189f9488421 (opens in a new tab)