ALSA: caiaq: fix stack out-of-bounds read in init_card
Summary
| CVE | CVE-2026-31778 |
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-05-01 15:16:41 UTC |
| Updated | 2026-05-01 15:24:14 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved:
ALSA: caiaq: fix stack out-of-bounds read in init_card
The loop creates a whitespace-stripped copy of the card shortname
where `len < sizeof(card->id)` is used for the bounds check. Since
sizeof(card->id) is 16 and the local id buffer is also 16 bytes,
writing 16 non-space characters fills the entire buffer,
overwriting the terminating nullbyte.
When this non-null-terminated string is later passed to
snd_card_set_id() -> copy_valid_id_string(), the function scans
forward with `while (*nid && ...)` and reads past the end of the
stack buffer, reading the contents of the stack.
A USB device with a product name containing many non-ASCII, non-space
characters (e.g. multibyte UTF-8) will reliably trigger this as follows:
BUG: KASAN: stack-out-of-bounds in copy_valid_id_string
sound/core/init.c:696 [inline]
BUG: KASAN: stack-out-of-bounds in snd_card_set_id_no_lock+0x698/0x74c
sound/core/init.c:718
The off-by-one has been present since commit bafeee5b1f8d ("ALSA:
snd_usb_caiaq: give better shortname") from June 2009 (v2.6.31-rc1),
which first introduced this whitespace-stripping loop. The original
code never accounted for the null terminator when bounding the copy.
Fix this by changing the loop bound to `sizeof(card->id) - 1`,
ensuring at least one byte remains as the null terminator. |
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|
| CNA |
Linux |
Linux |
affected bafeee5b1f8d32cbf791c322b40a6fa91d8ccf7a 02d9c5b0b5553a391448b6d655262bd829f90234 git |
Not specified |
| CNA |
Linux |
Linux |
affected bafeee5b1f8d32cbf791c322b40a6fa91d8ccf7a 3f7f8bae0d52cbd07ab04b76b6aac89ef98ee9f6 git |
Not specified |
| CNA |
Linux |
Linux |
affected bafeee5b1f8d32cbf791c322b40a6fa91d8ccf7a 66194c2575a4f567577ae70b1d7561163ce791a6 git |
Not specified |
| CNA |
Linux |
Linux |
affected bafeee5b1f8d32cbf791c322b40a6fa91d8ccf7a a82c1bce2d1299dd3c686a8fe48cf75b79a403c7 git |
Not specified |
| CNA |
Linux |
Linux |
affected bafeee5b1f8d32cbf791c322b40a6fa91d8ccf7a 3178b62e2e31bab39f63d4c8e54bf4ee0a425627 git |
Not specified |
| CNA |
Linux |
Linux |
affected bafeee5b1f8d32cbf791c322b40a6fa91d8ccf7a 3afa2e67f3523a980a2f90fd63c22322ac2b9ce0 git |
Not specified |
| CNA |
Linux |
Linux |
affected bafeee5b1f8d32cbf791c322b40a6fa91d8ccf7a 7594a6464873d90fd229e5b94cdd3b92c9feabed git |
Not specified |
| CNA |
Linux |
Linux |
affected bafeee5b1f8d32cbf791c322b40a6fa91d8ccf7a 45424e871abf2a152e247a9cff78359f18dd95c0 git |
Not specified |
| CNA |
Linux |
Linux |
affected 2.6.31 |
Not specified |
| CNA |
Linux |
Linux |
unaffected 2.6.31 semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 5.10.253 5.10.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 5.15.203 5.15.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.1.168 6.1.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.6.134 6.6.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.12.81 6.12.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.18.22 6.18.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 6.19.12 6.19.* semver |
Not specified |
| CNA |
Linux |
Linux |
unaffected 7.0 * original_commit_for_fix |
Not specified |
References
| Reference | Source | Link | Tags |
|---|
| git.kernel.org/stable/c/66194c2575a4f567577ae70b1d7561163ce791a6 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/45424e871abf2a152e247a9cff78359f18dd95c0 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/a82c1bce2d1299dd3c686a8fe48cf75b79a403c7 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/3afa2e67f3523a980a2f90fd63c22322ac2b9ce0 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/02d9c5b0b5553a391448b6d655262bd829f90234 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/3178b62e2e31bab39f63d4c8e54bf4ee0a425627 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/3f7f8bae0d52cbd07ab04b76b6aac89ef98ee9f6 |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| git.kernel.org/stable/c/7594a6464873d90fd229e5b94cdd3b92c9feabed |
416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
git.kernel.org |
|
| CVE Program record |
CVE.ORG |
www.cve.org |
canonical |
| NVD vulnerability detail |
NVD |
nvd.nist.gov |
canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.