ALSA: seq: Don't leak the extension cell pointer in the bounce payload
Key facts
- Attack vector
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- Privileges required
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- User interaction
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- Attack complexity
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- Impact type
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- Confidentiality · integrity · availability
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- Fix status
- Partial Red Hat: 2 without a fix
No CVSS vector from any source. Fix status from CNA and Red Hat.
Summary
In the Linux kernel, the following vulnerability has been resolved: ALSA: seq: Don't leak the extension cell pointer in the bounce payload The bounce_error_event() embeds the failed event in the bounce payload by pointing data.ext.ptr at it. When that event is a queued variable-length event, its own data.ext.ptr holds the address of its first extension cell, put there by snd_seq_event_dup(). The payload goes out verbatim through snd_seq_expand_var_event(), so the address reaches userspace. That is the same address commit 705dd6dcbc0e ("ALSA: seq: Clear variable event pointer on read") removed from the event header. The read path still clears it there, just above the call that expands the payload. Embed a sanitised copy instead, treated exactly as snd_seq_read() treats the header. A stack copy is enough because delivery is synchronous and snd_seq_event_dup() copies before returning. An unprivileged client reaches this by setting SNDRV_SEQ_FILTER_BOUNCE, queueing a variable-length event to a port that does not exist and reading the bounce back. Eight bytes on 64-bit, from its own pool.
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
Remediation
- Fix · CNA Linux (Linux) Fixed in 6.12.110, 6.18.52, 6.7, 7.2
- Fix · CNA Linux (Linux) Fixed in 6.12.110, 6.18.52, 7.2.6, 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 9 | Affected | No fix yet: Fix deferred |
Not affected: 6 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 7
- Red Hat Enterprise Linux 8
- Red Hat Enterprise Linux 9
- Red Hat OpenShift Container Platform 4
- Red Hat OpenShift Container Platform 5
Timeline
- 2026-10-02 Threatist record created from CVE-2026-90220
- 2026-10-03 Alias added: GHSA-r7hx-2638-9jpm
- 2026-10-13 Affected versions changed · Red Hat
- 2026-10-13 CVSS score added · Red Hat
- 2026-10-19 Fix available: Linux/[email protected] · CNA
- 2026-10-21 Fix available: Linux/[email protected] · CNA
- 2026-10-30 Fix available: Linux/Linux@c92b2e6e418a3885758438dddcead6e954a9e095 · CNA
- 2026-10-30 1 new reference · CNA
- 2026-11-06 Affected versions changed · Red Hat
References
Other 5
- https://git.kernel.org/stable/c/c92b2e6e418a3885758438dddcead6e954a9e095
- https://git.kernel.org/stable/c/42c3f856d13a91a0d4c302a0c6854813621136db
- https://git.kernel.org/stable/c/b1e8d40663997aacaa198f37ce6893e07aaba77a
- https://git.kernel.org/stable/c/6e6e471eef1d5d8cb056c7d364023fe048249204
- https://git.kernel.org/stable/c/59e1592d3c270ff4642d5d6dc55c545306eb0693
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-2026-90220 · CVE Program
- CVE-2026-90220 · NVD
- FIRST EPSS
- GHSA-r7hx-2638-9jpm · GitHub Advisory Database · CC BY 4.0
- CVE-2026-90220 · Red Hat security data · CC BY 4.0
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