How severe is CVE-2023-2640?

CVE-2023-2640 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-2640 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 16% (96th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-2640?

CVE-2023-2640 affects Canonical Ubuntu Linux. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-2640?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2023-2640 published?

CVE-2023-2640 was published on 2023-07-26 and last updated on 2026-06-17.

CVE-2023-2640

CVE-2023-2640 is a high-severity vulnerability in Canonical Ubuntu Linux with a CVSS 3.x base score of 7.8. Its EPSS exploit-prediction score of 16% places it in the 96th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-863.

Key facts

Severity: High (CVSS 3.x base score 7.8)
EPSS exploit prediction: 16% (96th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-863
Affected product: Canonical Ubuntu Linux
Published: 2023-07-26
Last modified: 2026-06-17

Description

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 on the upper files without the appropriate security checks.

Frequently asked questions

What is 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 on the upper files without the appropriate security checks.
How severe is CVE-2023-2640?: CVE-2023-2640 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-2640 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 16% (96th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-2640?: CVE-2023-2640 affects Canonical Ubuntu Linux. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-2640?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2023-2640 published?: CVE-2023-2640 was published on 2023-07-26 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:canonical:ubuntu_linux:23.04:*:*:*:*:*:*:*

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