Unknown

CVE-2025-40275 — ALSA: usb-audio: Fix NULL pointer dereference in snd_usb_mixer_controls_badd

In the Linux kernel, the following vulnerability has been resolved: ALSA: usb-audio: Fix NULL pointer dereference in snd_usb_mixer_controls_badd In snd_usb_create_streams(), for UAC version 3 devices, the Interface Association Descriptor (IAD) is retrieved via usb_ifnum_to_if(). If this call fails, a fallback routine attempts to obtain the IAD from the next interface and sets a BADD profile. However, snd_usb_mixer_controls_badd() assumes that the IAD retrieved from usb_ifnum_to_if() is always valid, without performing a NULL check. This can lead to a NULL pointer dereference when usb_ifnum_to_if() fails to find the interface descriptor. This patch adds a NULL pointer check after calling usb_ifnum_to_if() in snd_usb_mixer_controls_badd() to prevent the dereference. This issue was discovered by syzkaller, which triggered the bug by sending a crafted USB device descriptor.

Published Dec 6, 2025 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: Linux

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.2% (30-day exploitation probability)+1

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.2%

ahead of 9% of scored CVEs · Oct 15, 2026

Affects

Linux

CVSS base

—

Score not published yet.

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Linux	Linux	≥ 17156f23e93c0f59e06dd2aaffd06221341caaee and < 23aea9c74aeea2625aaf4fbcc6beb9d09e30f9e4≥ 17156f23e93c0f59e06dd2aaffd06221341caaee and < c5c08965ab96b16361e69a1e2a0e89dbcb99b5a6≥ 17156f23e93c0f59e06dd2aaffd06221341caaee and < 9f282104627be5fbded3102ff9004f753c55a063≥ 17156f23e93c0f59e06dd2aaffd06221341caaee and < 2762d3ea9c929ca4094541ca517c317ffa94625b≥ 17156f23e93c0f59e06dd2aaffd06221341caaee and < 57f607c112966c21240c424b33e2cb71e121dcf0≥ 17156f23e93c0f59e06dd2aaffd06221341caaee and < cbdbfc756f2990942138ed0138da9303b4dbf9ff≥ 17156f23e93c0f59e06dd2aaffd06221341caaee and < 85568535893600024d7d8794f4f8b6428b521e0c≥ 17156f23e93c0f59e06dd2aaffd06221341caaee and < 632108ec072ad64c8c83db6e16a7efee29ebfb74 and 1 more version 4.18	Vulnerable	CVE Program (cve.org) e CISA ADP

EPSS over time FIRST

Oct 13, 2026 → Oct 15, 2026 · 3 reading(s) · max 0.20%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Not enough vector or weakness data: use the affected application’s logs as a starting point.

application logs

Timeline

What happened to this CVE, newest first.

2026
Record published
Oct 13, 2026
Affected products added · linux/linux
Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
Source status changed · → Deferred
Oct 13, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 13, 2026 · NIST National Vulnerability Database
2025
CVE published
Dec 6, 2025 · Linux

Source activity

Repeated readings are counted rather than listed.

1× References added · Oct 15, 2026 – Oct 15, 2026
1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

10 on the record

git.kernel.org/stable/c/2762d3ea9c929ca4094541ca517c317ffa94625b
NIST National Vulnerability Database
git.kernel.org/stable/c/57f607c112966c21240c424b33e2cb71e121dcf0
NIST National Vulnerability Database
git.kernel.org/stable/c/23aea9c74aeea2625aaf4fbcc6beb9d09e30f9e4
NIST National Vulnerability Database
github.com/advisories/GHSA-x49w-vx84-7x88
GitHub Security Advisories
git.kernel.org/stable/c/cbdbfc756f2990942138ed0138da9303b4dbf9ff
NIST National Vulnerability Database
git.kernel.org/stable/c/85568535893600024d7d8794f4f8b6428b521e0c
NIST National Vulnerability Database
git.kernel.org/stable/c/9f282104627be5fbded3102ff9004f753c55a063
NIST National Vulnerability Database
git.kernel.org/stable/c/c5c08965ab96b16361e69a1e2a0e89dbcb99b5a6
NIST National Vulnerability Database
nvd.nist.gov/vuln/detail/CVE-2025-40275
GitHub Security Advisories
git.kernel.org/stable/c/632108ec072ad64c8c83db6e16a7efee29ebfb74
NIST National Vulnerability Database

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 12h
Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 12h
Unknown CVE-2026-98424 wifi: cfg80211: undo netns switch if renaming the wiphy fails 1d
Unknown CVE-2026-98425 wifi: mac80211: don't warn when an IBSS has no channel to scan 1d
Unknown CVE-2026-98426 wifi: mwifiex: fix IRQ leak using wrong index in MSI-X error path 1d
Unknown CVE-2026-98427 net/sched: codel: bound the dropping loop per dequeue call 1d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No CVSS score published by NVD, the CNA, CISA or GitHub so far.
No fixed version, patch or mitigation documented.
No CISA SSVC assessment.
No CWE classification.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2025-40275 is "ALSA: usb-audio: Fix NULL pointer dereference in snd_usb_mixer_controls_badd", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.20% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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