CVE-2026-74339
ALSA: seq: Clear variable event pointer on read
Description
In the Linux kernel, the following vulnerability has been resolved: ALSA: seq: Clear variable event pointer on read snd_seq_read() copies a queued variable-length event header to userspace before expanding the payload. Queued variable-length events use SNDRV_SEQ_EXT_CHAINED internally, and data.ext.ptr points at the first extension cell. The read side strips SNDRV_SEQ_EXT_* bits from data.ext.len before the copy, but it leaves data.ext.ptr untouched. A userspace sequencer client can therefore write a direct variable event to itself and read back the extension-cell kernel address from the returned header. Clear the temporary header pointer before copy_to_user(). The original queued event remains unchanged and is still passed to snd_seq_expand_var_event(), so payload expansion keeps using the internal chain.
INFO
Published Date :
Aug. 15, 2026, 6:22 a.m.
Last Modified :
Aug. 15, 2026, 6:22 a.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Affected Products
The following products are affected by CVE-2026-74339
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
Solution
- Clear temporary header pointer before copy_to_user().
- Ensure original event remains unchanged for expansion.
- Update the Linux kernel to the latest version.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-74339.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-74339 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-74339
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-74339 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-74339 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 15, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '1da177e4c3f41524e886b7f1b8a0c1fc7321cac2', 'lessThan': '14fe4f75fd5309d6b75f8e840ada88912b374207', 'versionType': 'git'}, {'status': 'affected', 'version': '1da177e4c3f41524e886b7f1b8a0c1fc7321cac2', 'lessThan': 'f29243c211928114f8b906e0a3fee77c236f14c8', 'versionType': 'git'}, {'status': 'affected', 'version': '1da177e4c3f41524e886b7f1b8a0c1fc7321cac2', 'lessThan': 'e0c3edd86414534cfd179fefe45b38c29c01ae7a', 'versionType': 'git'}, {'status': 'affected', 'version': '1da177e4c3f41524e886b7f1b8a0c1fc7321cac2', 'lessThan': '6b52211eba213c461f68922708a99d8190c1fcd5', 'versionType': 'git'}, {'status': 'affected', 'version': '1da177e4c3f41524e886b7f1b8a0c1fc7321cac2', 'lessThan': '74ac1ce1f4afdb3b80b6742fa28fb86c8c51d31b', 'versionType': 'git'}, {'status': 'affected', 'version': '1da177e4c3f41524e886b7f1b8a0c1fc7321cac2', 'lessThan': 'c2ac9287e89916da684c2a548798351e63eb59ee', 'versionType': 'git'}, {'status': 'affected', 'version': '1da177e4c3f41524e886b7f1b8a0c1fc7321cac2', 'lessThan': '705dd6dcbc0ea87351c660c1a6443f85f1001c76', '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': '5.15.212', 'versionType': 'semver', 'lessThanOrEqual': '5.15.*'}, {'status': 'unaffected', 'version': '6.1.178', 'versionType': 'semver', 'lessThanOrEqual': '6.1.*'}, {'status': 'unaffected', 'version': '6.6.145', '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-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['sound/core/seq/seq_clientmgr.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: ALSA: seq: Clear variable event pointer on read snd_seq_read() copies a queued variable-length event header to userspace before expanding the payload. Queued variable-length events use SNDRV_SEQ_EXT_CHAINED internally, and data.ext.ptr points at the first extension cell. The read side strips SNDRV_SEQ_EXT_* bits from data.ext.len before the copy, but it leaves data.ext.ptr untouched. A userspace sequencer client can therefore write a direct variable event to itself and read back the extension-cell kernel address from the returned header. Clear the temporary header pointer before copy_to_user(). The original queued event remains unchanged and is still passed to snd_seq_expand_var_event(), so payload expansion keeps using the internal chain. Added Reference https://git.kernel.org/stable/c/14fe4f75fd5309d6b75f8e840ada88912b374207 Added Reference https://git.kernel.org/stable/c/6b52211eba213c461f68922708a99d8190c1fcd5 Added Reference https://git.kernel.org/stable/c/705dd6dcbc0ea87351c660c1a6443f85f1001c76 Added Reference https://git.kernel.org/stable/c/74ac1ce1f4afdb3b80b6742fa28fb86c8c51d31b Added Reference https://git.kernel.org/stable/c/c2ac9287e89916da684c2a548798351e63eb59ee Added Reference https://git.kernel.org/stable/c/e0c3edd86414534cfd179fefe45b38c29c01ae7a Added Reference https://git.kernel.org/stable/c/f29243c211928114f8b906e0a3fee77c236f14c8