What is CVE-2023-2640?

CVE-2023-2640 is a high-severity vulnerability in Canonical Ubuntu Kernel, classified under Incorrect Authorization. CVSS score: 7.8/10. Published 2023-07-26.

How severe is CVE-2023-2640?

High severity. CVSS v3 base score is 7.8 out of 10.

Is CVE-2023-2640 known to be exploited?

64 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Auth bypass in Canonical Ubuntu Kernel

CVE-2023-2640

On Ubuntu kernels carrying both c914c0e27eb0 and "UBUNTU: SAUCE: overlayfs: Skip permission checking for trusted.overlayfs.* xattrs", an unprivileged user may set privileged extended attributes on the mounted files, leading them to be set…

Vulnerability class: Broken Access Control

EPSS: 0.924 (99.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Canonical Ubuntu Kernel — versions 0

Weakness classification (CWE)

CWE-863 — Incorrect Authorization

Public proof-of-concept exploits

References

ubuntu.com/security/notices/USN-6250-1 (vendor-advisory)
cve.mitre.org/cgi-bin/cvename.cgi (issue-tracking)
wiz.io/blog/ubuntu-overlayfs-vulnerability (technical-description)
lists.ubuntu.com/archives/kernel-team/2023-July/140923.html (mailing-list)

Frequently asked questions

What is CVE-2023-2640?: CVE-2023-2640 is a high-severity vulnerability in Canonical Ubuntu Kernel, classified under Incorrect Authorization. CVSS score: 7.8/10. Published 2023-07-26.
How severe is CVE-2023-2640?: High severity. CVSS v3 base score is 7.8 out of 10.
Is CVE-2023-2640 known to be exploited?: 64 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.