SB2026072601 - Multiple vulnerabilities in junrar

Description

This security bulletin contains information about 2 vulnerabilities.

1) Path traversal (CVE-ID: N/A)

CWE-ID: CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

CVSSv4: 6.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to create directories outside the intended extraction directory.

The vulnerability exists due to path traversal in LocalFolderExtractor makeFile() and createFile() when extracting a crafted RAR archive. A remote attacker can supply a malicious RAR archive to create directories outside the intended extraction directory.

This can be used for filesystem pollution or file-vs-directory squatting.

2) Infinite loop (CVE-ID: N/A)

CWE-ID: CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')

CVSSv4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to improper control flow management in the RarVM.ExecuteCode loop in src/main/java/com/github/junrar/unpack/vm/RarVM.java when extracting a crafted RAR4 archive containing jump instructions. A remote attacker can provide a specially crafted RAR archive to cause a denial of service.

The issue can cause an extraction thread to spin indefinitely, consuming CPU and blocking the process.

Remediation

Install update from vendor's website.

References

• https://github.com/junrar/junrar/security/advisories/GHSA-89m4-43j5-vhhx
• https://github.com/junrar/junrar/security/advisories/GHSA-h9h9-2rmf-rvhp