How severe is CVE-2023-0266?

CVE-2023-0266 has a CVSS 3.x base score of 7.9, rated high severity. It is exploitable over an adjacent network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity high, and availability high.

Is CVE-2023-0266 being actively exploited?

Yes. CVE-2023-0266 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2023-03-30, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2023-0266?

CVE-2023-0266 primarily affects Debian Debian Linux. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-0266?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2023-0266 have an EU (EUVD) identifier?

Yes. CVE-2023-0266 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-12345. It is also flagged as exploited in the EUVD (since 2023-03-30).

When was CVE-2023-0266 published?

CVE-2023-0266 was published on 2023-01-30 and last updated on 2026-06-17.

CVE-2023-0266

CVE-2023-0266 is a high-severity vulnerability in Debian Debian Linux with a CVSS 3.x base score of 7.9. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2023-03-30). The underlying weakness is classified as CWE-416.

Key facts

Severity: High (CVSS 3.x base score 7.9)
EPSS exploit prediction: 4% (88th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2023-03-30)
EU (EUVD) id: EUVD-2023-12345
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2023-03-30)
Weakness: CWE-416
Affected product: Debian Debian Linux
Published: 2023-01-30
Last modified: 2026-06-17

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

Frequently asked questions

What is CVE-2023-0266?: 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
How severe is CVE-2023-0266?: CVE-2023-0266 has a CVSS 3.x base score of 7.9, rated high severity. It is exploitable over an adjacent network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity high, and availability high.
Is CVE-2023-0266 being actively exploited?: Yes. CVE-2023-0266 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2023-03-30, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2023-0266?: CVE-2023-0266 primarily affects Debian Debian Linux. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-0266?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2023-0266 have an EU (EUVD) identifier?: Yes. CVE-2023-0266 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-12345. It is also flagged as exploited in the EUVD (since 2023-03-30).
When was CVE-2023-0266 published?: CVE-2023-0266 was published on 2023-01-30 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*

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