CVE-2026-68429 json
drm/dp_mst: Handle torn-down topology gracefully in drm_dp_mst_topology_queue_probe()
published 2026-08-12 2 mo ago modified 2026-11-06 2 d ago also EUVD-2026-57037
- cvss
- —
- not scored
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 6%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- Linux Linux 6.6.148, 6.12.101, 6.18.42, 7.1.6, 7.2
- linux Debian 13 6.12.101-1
- linux Debian 14 7.1.6-1
- linux-6.12 Debian 12 6.12.101-1~deb12u1
debian advisories DEBIAN-CVE-2026-68429
- linux Ubuntu 24.04 LTS 6.8.0-147.147
- linux Ubuntu 26.04 LTS 7.0.0-38.38
- linux-aws Ubuntu 24.04 LTS 6.8.0-1067.70
- linux-aws Ubuntu 26.04 LTS 7.0.0-1014.14
- linux-gcp Ubuntu 24.04 LTS 6.8.0-1071.79
- linux-gcp Ubuntu 26.04 LTS 7.0.0-1014.14
- linux-gke Ubuntu 24.04 LTS 6.8.0-1066.74
- linux-gke Ubuntu 26.04 LTS 7.0.0-1008.9
ubuntu advisories UBUNTU-CVE-2026-68429
Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
- kernel-64kb SLE Module for Basesystem 15 SP7 6.4.0-150700.53.81.1
- kernel-syms SLE Module for Development Tools 15 SP7 6.4.0-150700.53.81.1
- kernel-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.53.81.1
- kernel-source SLE Module for Development Tools 15 SP7, SLE Module for Basesystem 15 SP7 6.4.0-150700.53.81.1
- kernel-default SLE Workstation Extension 15 SP7, SLE Module for Legacy 15 SP7, SLE Module for Basesystem 15 SP7 +2 more 6.4.0-150700.53.81.1
- kernel-zfcpdump SLE Module for Basesystem 15 SP7 6.4.0-150700.53.81.1
- kernel-obs-build SLE Module for Development Tools 15 SP7 6.4.0-150700.53.81.1
- kernel-default-base SLE Module for Basesystem 15 SP7 6.4.0-150700.53.81.1.150700.17.45.1
suse advisories SUSE-SU-2026:4254-1SUSE-SU-2026:23887-1SUSE-SU-2026:23902-1SUSE-SU-2026:23897-1SUSE-SU-2026:23881-1SUSE-SU-2026:4120-1
- kernel-rt openSUSE Leap 16.0 6.12.0-160000.38.1
- dtb-aarch64 openSUSE Leap 16.0 6.12.0-160000.38.1
- kernel-64kb openSUSE Leap 16.0 6.12.0-160000.38.1
- kernel-syms openSUSE Leap 16.0 6.12.0-160000.38.1
- kernel-azure openSUSE Leap 16.0 6.12.0-160000.38.1
- kernel-obs-qa openSUSE Leap 16.0 6.12.0-160000.38.1
- kernel-source openSUSE Leap 16.0 6.12.0-160000.38.1
- kernel-default openSUSE Leap 16.0 6.12.0-160000.38.1
opensuse advisories openSUSE-SU-2026:21910-1
- git.kernel.org/stable/c/b1d05cc61dfa6c4bd5e67855bec6a03e955f512d commit
- git.kernel.org/stable/c/4ed6d08c4a59ee6a8cb806347f6d9873de5d229e commit
- git.kernel.org/stable/c/8c6d84a54823cd839e6ce22af559925f1320c310 commit
- git.kernel.org/stable/c/afdff9103818656627920c21822e48a6dae2906f commit
- git.kernel.org/stable/c/613059875958e7b217b250ed14c3b189f9488421 commit
Vendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2026-68429 updated cvss 5.5
kernel: drm/dp_mst: Handle torn-down topology gracefully in drm_dp_mst_topology_queue_probe()
-
Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more Red Hat Enterprise Linux 10 kernel 6.12.0-211.46.1.el10_2 Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-9 Red Hat OpenShift Container Platform 5 openshift/ose-rhel-coreos-9affected: no fix available “Fix deferred”
-
Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +2 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +9 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +30 more Red Hat Enterprise Linux 9 kernel-rt, kernel-rt-selftests-internal Red Hat Enterprise Linux for NVIDIA 26 kernel 6.12.0-211.46.1.el10_2 Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-8not affected: vulnerable code not present
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2 d ago
Exploit prediction
0.17% chance of exploitation in the next 30 days, higher than 6% of all scored CVEs (FIRST EPSS, 2026-11-08).
Affected products
- Linux Linux
Classification
- Technology feeds
References
- git.kernel.org /stable/c/b1d05cc61dfa6c4bd5e67855bec6a03e955f512d
- git.kernel.org /stable/c/4ed6d08c4a59ee6a8cb806347f6d9873de5d229e
- git.kernel.org /stable/c/8c6d84a54823cd839e6ce22af559925f1320c310
- git.kernel.org /stable/c/afdff9103818656627920c21822e48a6dae2906f
- git.kernel.org /stable/c/613059875958e7b217b250ed14c3b189f9488421
Sources
- CVE List CVE-2026-68429
- NVD CVE-2026-68429
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.