CVE-2023-0266: Linux Kernel · Use After Free
Affects Linux KernelSource CVE Database V5
Exploited in the wild · KEV due 20 Apr 2023 · 3% EPSS : apply the vendor's fix or mitigations to Linux Kernel now.
Data as of 25 Oct 2026, 19:02 UTC
- KEV deadline
- US federal agencies must patch by this date; a sensible deadline for everyone else.
- EPSS
- 3.6% chance of exploitation in 30 days – higher than 89% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:C/C:L/I:H/A:HExploitation evidence
t = 0 is the CVE’s publication on cve.org
Disclosed: evidence found.
CVE published 30 Jan 2023
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: evidence found.
Listed in CISA KEV 59 days after disclosure
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
Timeline
CVE ID reserved
by Google
, 17 days before disclosure
CVE published
on cve.org
, t = 0
Added to CISA KEV (opens in a new tab)
exploitation confirmed
, 59 days after disclosure
KEV remediation due
US federal deadline
, 80 days after disclosure
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), CISA KEV (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-25.
What to do
Apply updates per vendor instructions.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
GitHubtorvalds/linuxpkg:github/torvalds/linuxOther threats | Affected
| Fixed in– |
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
Description
A use after free vulnerability exists in the ALSA PCM package in the Linux Kernel. SNDRV_CTL_IOCTL_ELEM_{READ|WRITE}32 is missing locks that can be used in a use-after-free that can result in a priviledge escalation to gain ring0 access from the system user. We recommend upgrading past commit 56b88b50565cd8b946a2d00b0c83927b7ebb055e
References
- github.com/torvalds/linux/commit/becf9e5d553c2389d857a3c178ce80fdb34a02e1 (opens in a new tab)
- git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git/tree/queue-5.10/alsa-pcm-move-rwsem-lock-inside-snd_ctl_elem_read-to-prevent-uaf.patch?id=72783cf35e6c55bca84c4bb7b776c58152856fd4 (opens in a new tab)
- github.com/torvalds/linux/commit/56b88b50565cd8b946a2d00b0c83927b7ebb055e (opens in a new tab)
- lists.debian.org/debian-lts-announce/2023/05/msg00006.html (opens in a new tab)
- cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-0266 (opens in a new tab)