CVE-2026-46048 — ALSA: caiaq: fix usb_dev refcount leak on probe failure
In the Linux kernel, the following vulnerability has been resolved: ALSA: caiaq: fix usb_dev refcount leak on probe failure create_card() takes a reference on the USB device with usb_get_dev() and stores the matching usb_put_dev() in card_free(), which is installed as the snd_card's ->private_free destructor. However, ->private_free is only assigned near the end of init_card(), after several failure points (usb_set_interface(), EP type checks, usb_submit_urb(), the EP1_CMD_GET_DEVICE_INFO exchange, and its timeout). When any of those fail, init_card() returns an error to snd_probe(), which calls snd_card_free(card). Because ->private_free is still NULL, card_free() never runs, the usb_get_dev() reference is not dropped, and the struct usb_device leaks along with its descriptor allocations and device_private. syzbot reproduces this with a malformed UAC3 device whose only valid altsetting is 0; init_card()'s usb_set_interface(usb_dev, 0, 1) call fails with -EIO and triggers the leak. Move the ->private_free assignment into create_card(), immediately after usb_get_dev(), so that every error path reaching snd_card_free() balances the reference. card_free()'s callees (snd_usb_caiaq_input_free, free_urbs, kfree) already tolerate the partially-initialized state because the chip private area is zero-initialized by snd_card_new().
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+1
- Technical severity (medium)+3
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.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
- Documented patch — git.kernel.org (NIST National Vulnerability Database)
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, Linux Linux Kernel).
- Apply the fixed version or the patch documented under Remediation.
- 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 |
≥ f6634af5de728a46792f674a66d7843570cb68f7 and < 50c6a1f05973f56d23280c9d7645a7a5734e0907≥ 7.0.2 and < 7.0.4≥ 6.18.25 and < 6.18.27≥ 6.12.84 and < 6.12.86≥ 6.6.136 and < 6.6.140≥ 80bb50e2d459213cccff3111d5ef98ed4238c0d5 and < 7a5f1cd22d47f8ca4b760b6334378ae42c1bd24b≥ 59b622a043cffc58b7638cd85ae6c30a0904f8e6 and < 21ca595aafa40d3ac70eab1f4cb62cc00ca21657≥ 6473ed16df1fe88051140611b3eb9a49be7f429e and < 6153878c5255bb69b7d0868105ca078ef13cbcf8 and 4 more≥ 1d9be95aee6c6246a21752e60c9519902649f482 and < da3b8fd6a202d94fef11a443abc9171c52426a1c≥ ac7345f68cda6989016d85d63f7b244c064aa8f6 and < a8d907acc3e5a078c2e5637ff60c30c6d2ddc23a≥ dbcf7588e8dea017ddb3f18ec2766f7d2e5f2a0e and < 6fa8dff64fb6c401ced40a05797b327659317498≥ 493b3a682ededc804555755f5d2193201339612d and < c874db8a1d2f9f08161470d00cfe8db2f5cca2cc |
Vulnerable | CVE Program (cve.org) e CISA ADP |
| Linux | Linux Kernel | ≥ 6.6.136 and < 6.6.140version 7.1-rc1≥ 7.0.2 and < 7.0.4≥ 6.18.25 and < 6.18.27≥ 6.12.84 and < 6.12.86 | Vulnerable | NIST National Vulnerability Database |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 5.5 | CVSS 3.1 | Medium | 1.8 | 3.6 | nvd@nist.gov via NIST National Vulnerability Database |
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H (score shown at the top: nvd@nist.gov) EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.16%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · linux/linux
- Record published
- Fix documented
- CVSS changed · 5.5
- Source status changed · → Analyzed
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
8 on the record
- git.kernel.org/stable/c/da3b8fd6a202d94fef11a443abc9171c52426a1c
- git.kernel.org/stable/c/a8d907acc3e5a078c2e5637ff60c30c6d2ddc23a
- git.kernel.org/stable/c/21ca595aafa40d3ac70eab1f4cb62cc00ca21657
- git.kernel.org/stable/c/c874db8a1d2f9f08161470d00cfe8db2f5cca2cc
- git.kernel.org/stable/c/6153878c5255bb69b7d0868105ca078ef13cbcf8
- git.kernel.org/stable/c/7a5f1cd22d47f8ca4b760b6334378ae42c1bd24b
- git.kernel.org/stable/c/6fa8dff64fb6c401ced40a05797b327659317498
- git.kernel.org/stable/c/50c6a1f05973f56d23280c9d7645a7a5734e0907
Elsewhere on this site
Related CVEs (same products)
- Critical CVE-2026-99999 ipv4: validate checksum_start before completing checksum 9h
- Unknown CVE-2026-98432 ipv4: free inet_opt and ireq_opt after an RCU grace period 9h
- 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
- Unknown CVE-2026-98428 ALSA: usb: 6fire: Avoid embedded URBs 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 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-2026-46048 is "ALSA: caiaq: fix usb_dev refcount leak on probe failure", rated Medium. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 5.5 describes technical severity. EPSS 0.16% 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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