CVE-2026-98742 json
ALSA: seq: Serialize compat port-info ioctls
published 24d ago modified 12d ago also EUVD-2026-103827
- 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 7%
- public exploits
- 0
- none known
Summary
In the Linux kernel, the following vulnerability has been resolved:
ALSA: seq: Serialize compat port-info ioctls
The native sequencer ioctl path serializes handler calls with client->ioctl_mutex, but the translated port-info compat path invokes the same handlers through snd_seq_kernel_client_ctl() without taking that mutex.
This lets concurrent compat CREATE_PORT requests pass the port-count check before any request reaches the serialized insertion. The computed integer port index can then exceed the address field range and wrap to an existing index. Subsequent subscriber teardown can resolve the duplicate address to the wrong port and access a freed subscriber.
Take ioctl_mutex while dispatching converted port-info requests, matching the native ioctl path. All translated port-info commands share this helper, so their accesses to the client port state are serialized as well.
Patch / fix
- Linux Linux 3.3, 3.17, 3.19, 4.2, 4.5, 4.10, 4.15, 7.3
- linux Debian 13 6.12.113-1
- linux Debian 14 7.2.10-1
- linux-6.12 Debian 12 6.12.113-1~deb12u1
debian advisories DEBIAN-CVE-2026-98742
- linux Ubuntu 24.04 LTS 6.8.0-149.149
- linux Ubuntu 26.04 LTS 7.0.0-43.43
- linux-aws Ubuntu 24.04 LTS 6.8.0-1069.74
- linux-aws Ubuntu 26.04 LTS 7.0.0-1017.18
- linux-gcp Ubuntu 24.04 LTS 6.8.0-1073.81
- linux-gcp Ubuntu 26.04 LTS 7.0.0-1017.19
- linux-gke Ubuntu 24.04 LTS 6.8.0-1068.77
- linux-gke Ubuntu 26.04 LTS 7.0.0-1010.11
ubuntu advisories UBUNTU-CVE-2026-98742
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-source Linux Micro 6.0 6.4.0-159998.55.1
- kernel-default Linux Micro 6.0 6.4.0-159998.55.1
- kernel-kvmsmall Linux Micro 6.0 6.4.0-159998.55.1
- kernel-default-base Linux Micro 6.0 6.4.0-159998.55.1.159998.21.42
- kernel-64kb SLE Module for Basesystem 15 SP7 6.4.0-150700.53.90.1
- kernel-syms SLE Module for Development Tools 15 SP7 6.4.0-150700.53.90.1
- kernel-azure SLE Module for Public Cloud 15 SP7 6.4.0-150700.53.90.1
- kernel-source SLE Module for Development Tools 15 SP7, SLE Module for Basesystem 15 SP7 6.4.0-150700.53.90.1
suse advisories SUSE-SU-2026:24550-1SUSE-SU-2026:5091-1
- git.kernel.org/stable/c/14e178c60ba1cea49186fcfccac93d66aa94e9e0 commit
- git.kernel.org/stable/c/4980768c5d092493be0deb20d1ee86aa661466f8 commit
- git.kernel.org/stable/c/2c0cce3a5a660270d65729b0f318d4e01470479d commit
- git.kernel.org/stable/c/2db234e163f0d211b69a4eebbec8aacc5a54a80e commit
- git.kernel.org/stable/c/413211dd31cb2ef2fc99fb0aa1a037a97509502c commit
- git.kernel.org/stable/c/fc5c52848e405b6efb073db5035bb9ebaed11ec4 commit
- git.kernel.org/stable/c/702d92f361f65d9698c473c7599d471395dc4341 commit
- git.kernel.org/stable/c/95b2e0361c88753afa030c10698be0a1a5b67650 commit
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Check with FencerVendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2026-98742 updated cvss 4.7
kernel: kernel: Use-after-free via race condition in ALSA sequencer compatibility ioctls
-
Red Hat Enterprise Linux 10 kernelaffected: workaround, no fix available “Fix deferred”
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
Exploit prediction
0.18% chance of exploitation in the next 30 days, higher than 7% of all scored CVEs (FIRST EPSS, 2026-11-11).
Affected products
- Linux Linux
Classification
- Technology feeds
References
- git.kernel.org /stable/c/14e178c60ba1cea49186fcfccac93d66aa94e9e0
- git.kernel.org /stable/c/4980768c5d092493be0deb20d1ee86aa661466f8
- git.kernel.org /stable/c/2c0cce3a5a660270d65729b0f318d4e01470479d
- git.kernel.org /stable/c/2db234e163f0d211b69a4eebbec8aacc5a54a80e
- git.kernel.org /stable/c/413211dd31cb2ef2fc99fb0aa1a037a97509502c
- git.kernel.org /stable/c/fc5c52848e405b6efb073db5035bb9ebaed11ec4
- git.kernel.org /stable/c/702d92f361f65d9698c473c7599d471395dc4341
- git.kernel.org /stable/c/95b2e0361c88753afa030c10698be0a1a5b67650
Sources
- CVE List CVE-2026-98742
- NVD CVE-2026-98742
Fencer Intel 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.