Privilege Escalation Vulnerability in Ubuntu OverlayFS
CVE-2023-2640

7.8HIGH

Key Information:

Vendor

Canonical

Status
Ubuntu Kernel
Vendor
CVE Published:
26 July 2023

Badges

👾 Exploit Exists🟡 Public PoC🟣 EPSS 91%

What is CVE-2023-2640?

A vulnerability in Ubuntu's OverlayFS allows unprivileged users to bypass security checks, enabling them to set privileged extended attributes on files within the mounted filesystem. This flaw could lead to unauthorized access and manipulation of upper files, compromising the integrity and security of the system.

Affected Version(s)

Ubuntu Kernel Linux 0 < 6.2.0-26.26

Ubuntu Kernel Linux 0 < 6.0.0-1020.20

Ubuntu Kernel Linux 0 < 5.4.0-155.172

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2023-2640-CVE-2023-32629
Created by g1vi

Metasploit exploit module for CVE-2023-2640
Created by Rapid7

GameOverlayFS
Created by luanoliveira350

References

https://ubuntu.com/security/notices/USN-6250-1
vendor-advisory
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-2640
issue-tracking
https://wiz.io/blog/ubuntu-overlayfs-vulnerability
technical-description

EPSS Score

91% chance of being exploited in the next 30 days.

CVSS V3.1

Score:
7.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Local
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • 🟡

    Public PoC available

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Stonejiajia
Shir Tamari
Sagi Tzadik
.
CVE-2023-2640 : Privilege Escalation Vulnerability in Ubuntu OverlayFS