CVE-2023-0266: Linux Kernel Use-After-Free Vulnerability
- Is it exploited?
Yes. CISA added it to the Known Exploited Vulnerabilities catalog on , 59 days after the CVE record was published.
- How likely is exploitation in the next 30 days?
- 3.7%
EPSS score, percentile 89.6 of all scored records
- How severe?
- 7.9 High
CVSS v3.1 base score, given by the CNA
- What should I do?
CISA deadline . Apply updates per vendor instructions.
The CVE record links no vendor advisory, patch or mitigation.
- Which versions are affected?
Affected
- from 4.14 to before 56b88b50565c
Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of ; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of ; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of . About the data.
What to do
Required action, set by CISA
Apply updates per vendor instructions.
CISA due date for this action: .
Advisories and patches
The CVE record links no vendor advisory, patch or mitigation.
Linked from CISA's catalog entry
- https://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
- https://nvd.nist.gov/vuln/detail/CVE-2023-0266
Affected products and versions
As listed in the CVE record.
| Status | Versions |
|---|---|
| Affected | from 4.14 to before 56b88b50565c |
Versions not listed are: unaffected.
Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of . About the data.
About this vulnerability
Linux kernel contains a use-after-free vulnerability that allows for privilege escalation to gain ring0 access from the system user.
Summary: CISA's KEV catalog, as of .
- CISA added CVE-2023-0266 to its Known Exploited Vulnerabilities (KEV) catalog on 30 Mar 2023.
- CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
- The due date CISA sets for the required action is 20 Apr 2023.
- The CVE record was published on 30 Jan 2023, 59 days before it was added to KEV.
- The CVE record carries a CVSS v3.1 base score of 7.9 (High), given by its CNA.
- FIRST's EPSS model puts the probability of exploitation in the next 30 days at 3.7% (percentile 89.6), as of 28 Oct 2026.
- CISA's SSVC assessment in the CVE record: exploitation active, automatable no, technical impact total.
Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of ; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of ; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of . About the data.
Description
Use after free in SNDRV_CTL_IOCTL_ELEM in Linux Kernel
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
Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of . About the data.
Weakness
- CWE-416: Use After Free
Attack patterns (CAPEC)
- CAPEC-233: Privilege Escalation
CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.
Timeline
| Date | Event |
|---|---|
| CVE record published | |
| Added to CISA KEV | |
| CISA due date for the required action | |
| CVE record last updated |
References
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