SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2024-5102

A sym-linked file accessed via the repair function in Avast Antivirus <24.2 on Windows may allow user to elevate privilege to delete arbitrary files or run processes as NT AUTHORITY\SYSTEM.

HIGH 7.3EPSS 0.22%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.22%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A sym-linked file accessed via the repair function in Avast Antivirus <24.2 on Windows may allow user to elevate privilege to delete arbitrary files or run processes as NT AUTHORITY\SYSTEM. The vulnerability exists within the "Repair" (settings -> troubleshooting -> repair) feature, which attempts to delete a file in the current user's AppData directory as NT AUTHORITY\SYSTEM. A low-privileged user can make a pseudo-symlink and a junction folder and point to a file on the system. This can provide a low-privileged user an Elevation of Privilege to win a race-condition which will re-create the system files and make Windows callback to a specially-crafted file which could be used to launch a privileged shell instance. This issue affects Avast Antivirus prior to 24.2.

CVSS 4.0
7.3 HIGHCVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:A/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS
0.22% probability · 13th percentile
CISA KEV
Not listed
Weakness
CWE-1284, CWE-59
Affected
avast/antivirus
Source
security@nortonlifelock.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.