PT-2023-4040 · Canonical+2 · Ubuntu+2

Sagi Tzadik + 2 · Published 2023-06-06 · Updated 2026-05-22 · CVE-2023-2640

Positive Technologies (AI Summary)

CVSS v3.1

7.8

High

Base vector

AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Ubuntu kernels carrying both c914c0e27eb0 and "UBUNTU: SAUCE: overlayfs: Skip permission checking for trusted.overlayfs.* xattrs"

Description The issue is related to the overlayfs file system in Ubuntu kernels, where an unprivileged user may set privileged extended attributes on mounted files without proper security checks, potentially leading to arbitrary code execution or denial of service. This is due to a missing authorization check in the overlayfs file system.

Recommendations As a temporary workaround, consider disabling the overlayfs file system until a patch is available. Restrict access to the mounted files to minimize the risk of exploitation. Avoid using privileged extended attributes on the mounted files until the issue is resolved. At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

Incorrect Authorization

Weakness Enumeration

CWE-863

Related Identifiers

ALSA-2025_16880

BDU:2023-04338

CVE-2023-2640

USN-6248-1

USN-6250-1

USN-6260-1

USN-6285-1

USN-8255-1

USN-8255-2

USN-8255-3

USN-8275-1

USN-8297-1

ZDI-23-1009

Affected Products

Astra Linux

Linuxmint

Ubuntu

References · 170

• 🔥 https://github.com/rapid7/metasploit-framework/blob/master/modules/exploits/linux/local/gameoverlay_privesc.rb · Exploit
• 🔥 https://github.com/g1vi/CVE-2023-2640-CVE-2023-32629 · Exploit
• 🔥 https://github.com/luanoliveira350/GameOverlayFS · Exploit
• 🔥 https://github.com/OllaPapito/gameoverlay · Exploit
• 🔥 https://wiz.io/blog/ubuntu-overlayfs-vulnerability · Exploit
• https://ubuntu.com/security/CVE-2026-23089 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-23083 · Vendor Advisory
• https://ubuntu.com/security/notices/USN-8275-1 · Vendor Advisory
• https://ubuntu.com/security/CVE-2023-32629 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-23011 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-23093 · Vendor Advisory
• https://ubuntu.com/security/notices/USN-6250-1 · Vendor Advisory
• https://bdu.fstec.ru/vul/2023-04338 · Security Note
• https://ubuntu.com/security/CVE-2025-38408 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-23075 · Vendor Advisory