CVE-2024-5102: avast antivirus

Vulnerability summary

CVE-2024-5102 is a high (CVSS 7.3) vulnerability in avast antivirus. EPSS estimates a 0.22% chance of exploitation in the next 30 days, higher than 12.4% of scored vulnerabilities.

Timeline

1. 10-06-2024
   PublishedVulnerability first disclosed.
2. 01-08-2024
   Last modifiedVulnerability information updated.

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.

• CWE-1284Improper Validation of Specified Quantity in InputThe product receives input that is expected to specify a quantity (such as size or length), but it does not validate or incorrectly validates that the quantity has the required properties.
• CWE-59Improper Link Resolution Before File Access ('Link Following')The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.