ALSA: seq: Fix kernel heap address leak in bounce_error_event()
In the Linux kernel, the following vulnerability has been resolved: ALSA: seq: Fix kernel heap address leak in bounce_error_event() The comment above bounce_error_event() documents that user clients should receive SNDRV_SEQ_EVENT_BOUNCE with the original event embedded as variable-length data, while kernel clients should receive SNDRV_SEQ_EVENT_KERNEL_ERROR with a quoted kernel pointer. However, the implementation unconditionally uses SNDRV_SEQ_EVENT_KERNEL_ERROR with data.quote.event set to the raw struct snd_seq_event pointer for all clients. When a bounce error event is delivered to a USER_CLIENT via snd_seq_read(), the kernel heap address in data.quote.event is exposed to userspace through copy_to_user() in the fixed-length branch. This is a distinct leak path from the one addressed by commit 705dd6dcbc0e ("ALSA: seq: Clear variable event pointer on read"), which sanitizes data.ext.ptr in the variable-length branch of snd_seq_read(). The bounce_error_event() leak uses fixed-length events that take the else branch where no sanitization occurs. Differentiate the bounce event by client type. For USER_CLIENT, send SNDRV_SEQ_EVENT_BOUNCE with SNDRV_SEQ_EVENT_LENGTH_VARIABLE and data.ext pointing to the original event. The variable-length path in snd_seq_event_dup() copies the event data into chained cells, and snd_seq_expand_var_event() copies only the content -- never the pointer -- to userspace. For KERNEL_CLIENT, keep the existing SNDRV_SEQ_EVENT_KERNEL_ERROR behavior with
CVE-2026-74278
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-74278
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "eae296065ede41a24040e6a7c909ec970f78b4eb",
"versionType": "git"
},
{
"status": "affected",
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "93d260ce43a81df579c98bee92b91316df9c1c57",
"versionType": "git"
},
{
"status": "affected",
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "dae23c545eb5a2be3b27a82fd0f611894fb8ab69",
"versionType": "git"
},
{
"status": "affected",
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "0527a56cb327021cb73167cfddf0e49efa043500",
"versionType": "git"
},
{
"status": "affected",
"version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
"lessThan": "efc86691e4d8083d9e380ea95042c2cf679f65fd",
"versionType": "git"
}
],
"programFiles": [
"sound/core/seq/seq_clientmgr.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.12"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "2.6.12",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "6.6.160",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.97",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.40",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.5",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"sound/core/seq/seq_clientmgr.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-74278
Source reference:
/cveMetadata/cveId
Publisher severity
No explicit severity was provided.
- Event
- #46540 · Revision 1
- Added to Heist Feed
- Publisher date