CVE-2026-97931ALSA: us122l: Prevent write upgrades for read mappings
- 7.0HighCVSS base score
- 0.14%Exploitation in 30 daysEPSS · top 96% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
In the Linux kernel, the following vulnerability has been resolved: ALSA: us122l: Prevent write upgrades for read mappings The hwdep mmap callback rejects read-buffer mappings that are initially writable, but leaves VM_MAYWRITE set on mappings created with PROT_READ. A process that can open the hwdep node O_RDWR can later use mprotect() to make the mapping writable. The read allocation begins with struct usb_stream. Its read_size member is used by the fault handler to decide which pages belong to the read buffer. The read VMA intentionally remains expandable because pcm_usb_stream uses mremap() after reading that size. Changing read_size first can therefore map and access pages beyond the allocation. The same member is also consumed by usb_stream_free(), where changing it can make free_pages_exact() release pages outside the allocation. Clear VM_MAYWRITE for read-buffer mappings after rejecting an initially writable VMA. This keeps the separate output-buffer mapping writable while preventing later permission upgrades.
Timeline
ID reserved
By Linux
Published
- 24 days later
· 24 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| LinuxCNA (assigner) | 3.1 | High7.0 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Received | 3.1 | High7.0 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.14% · top 96% of all CVEs (13 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.0.
Affected products
- affected 030a07e441296c372f946cd4065b5d831d8dc40c – < cbc1f954ce67d739d41d1f0757d29850353ebb6a
- affected 030a07e441296c372f946cd4065b5d831d8dc40c – < becb89036a1320ef0a77da2d27935ac0704345c4
- affected 030a07e441296c372f946cd4065b5d831d8dc40c – < 6a5f5a5a32c78e67701f1d0f26bc87af68895604
- affected 030a07e441296c372f946cd4065b5d831d8dc40c – < 938e8d6cee8d36f24669dfdcd3717e081eb32d64
- affected 030a07e441296c372f946cd4065b5d831d8dc40c – < 64a87950239867682cde128020e1a47088295e5c
- affected 030a07e441296c372f946cd4065b5d831d8dc40c – < d9c537b14f4982f17b103e3a2cfeee4bee6bc026
- affected 030a07e441296c372f946cd4065b5d831d8dc40c – < 0eb9dd4774af0ac4d1fd105ef2b0a1f6cec06f2f
- affected 030a07e441296c372f946cd4065b5d831d8dc40c – < 71c610aeb1770302ac9c9e0b9a4ecd37f1311928
- affected 2.6.28
- unaffected < 2.6.28
- unaffected 5.10.271 – ≤ 5.10.*
- unaffected 5.15.222 – ≤ 5.15.*
- unaffected 6.1.189 – ≤ 6.1.*
- unaffected 6.6.158 – ≤ 6.6.*
- unaffected 6.12.111 – ≤ 6.12.*
- unaffected 6.18.53 – ≤ 6.18.*
- unaffected 7.2.7 – ≤ 7.2.*
- unaffected 7.3 – ≤ *
References
References8
- https://git.kernel.org/stable/c/cbc1f954ce67d739d41d1f0757d29850353ebb6a (opens in a new tab)
- https://git.kernel.org/stable/c/becb89036a1320ef0a77da2d27935ac0704345c4 (opens in a new tab)
- https://git.kernel.org/stable/c/6a5f5a5a32c78e67701f1d0f26bc87af68895604 (opens in a new tab)
- https://git.kernel.org/stable/c/938e8d6cee8d36f24669dfdcd3717e081eb32d64 (opens in a new tab)
- https://git.kernel.org/stable/c/64a87950239867682cde128020e1a47088295e5c (opens in a new tab)
- https://git.kernel.org/stable/c/d9c537b14f4982f17b103e3a2cfeee4bee6bc026 (opens in a new tab)
- https://git.kernel.org/stable/c/0eb9dd4774af0ac4d1fd105ef2b0a1f6cec06f2f (opens in a new tab)
- https://git.kernel.org/stable/c/71c610aeb1770302ac9c9e0b9a4ecd37f1311928 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-86785 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
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[](https://cveledger.app/cve/CVE-2026-97931)Record last updated .