Use-after-free in Linux kernel ALSA core after async card release
Key facts
- Attack vector
- —
- Privileges required
- —
- User interaction
- —
- Attack complexity
- —
- Impact type
- —
- Confidentiality · integrity · availability
- —
- Fix status
- Partial Red Hat: 7 without a fix
No CVSS vector from any source. Fix status from CNA and Red Hat.
Summary
The Linux kernel ALSA core, affected from 2.6.12, releases sound cards asynchronously when the device is closed, as the USB-audio driver does, while in-flight tasks may still access the card device after disconnection. This causes a use-after-free, which fuzzers reported. The fix takes a reference on the card device at initialization and releases it in the card destructor, so the device stays valid for the card's whole lifecycle.
Written with Claude Haiku 5.5 from the sources below · 2026-11-06
Description from the CNA
In the Linux kernel, the following vulnerability has been resolved: ALSA: core: Fix potential UAF after asynchronous card release Usually a sound driver releases the resources assigned to the card via snd_card_free(), and it synchronizes with the whole release procedure. However, when the card is released asynchronously via snd_card_free_when_closed() like USB-audio driver, the situation is slightly different; although the snd_card_disconnect() call at the disconnection guarantees that any newer accesses will be gated, the in-flight tasks might be still accessing to the underlying card->dev device even after the disconnection, which would cause a use-after-free in the end, as reported by fuzzers. For addressing the bug above, this patch takes the refcount of card->dev at initialization of the card object, and releases at its destructor. This assures the availability of the card->dev in its whole lifecycle.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
Remediation
Update the Linux kernel to 6.12.112, 6.18.54, 7.2.8 or 7.3, depending on the branch in use. Red Hat lists no fix planned for Red Hat Enterprise Linux 6 and no fix currently available for Red Hat Enterprise Linux 7, 8, 9 and 10 and for Red Hat OpenShift Container Platform 4 and 5.
Written with Claude Haiku 5.5 from the sources below · 2026-11-06
- Fix · CNA Linux (Linux) Fixed in 6.12.112, 6.18.54, 7.2.8, 7.3
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 6 | Affected | No fix planned: Out of support scope |
| Red Hat Enterprise Linux 7 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 4 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 5 | Affected | No fix yet: Fix deferred |
Timeline
- 2026-10-06 Threatist record created from CVE-2026-98266
- 2026-10-06 Alias added: GHSA-4mg3-v7f5-c2hj
- 2026-10-07 Fix available: Linux/Linux@0 · CNA
- 2026-10-11 Affected versions changed · Red Hat
- 2026-10-11 CVSS score added · Red Hat
- 2026-10-19 Fix available: Linux/[email protected] · CNA
- 2026-10-30 Affected versions changed · Red Hat
- 2026-11-03 Affected versions changed · Red Hat
- 2026-11-03 CVSS score changed · Red Hat
References
More Linux vulnerabilities
- TI-2025-26358 tls: fix handling of zero-length records on the rx_list KEVCVSS 3.1CRITICAL 9.8
- TI-2026-38352 netfilter: bridge: make ebt_snat ARP rewrite writable KEVCVSS 3.1HIGH 8.8
- TI-2021-02452 Incorrect authorization in Ubuntu linux kernel KEVCVSS 3.1HIGH 8.8
- TI-2013-05264 The (1) get_user and (2) put_user API functions in the Linux kernel before 3.5.5 on the… KEVCVSS 3.1HIGH 8.8
- TI-2022-00125 Integer overflow in kernel KEVCVSS 3.1HIGH 8.4
- TI-2013-01864 The perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9… KEVCVSS 3.1HIGH 8.4
Sources
- CVE-2026-98266 · CVE Program
- CVE-2026-98266 · NVD
- FIRST EPSS
- GHSA-4mg3-v7f5-c2hj · GitHub Advisory Database · CC BY 4.0
- CVE-2026-98266 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences