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CVE-2017-14122: Rarlab Unrar: Buffer overflow

CVE-2017-14122 is rated critical with a CVSS v3.1 base score of 9.1 and affects Rarlab Unrar, along with 1 other product in NVD’s configuration data. Per its scoring, it can be exploited over the network, without authentication, without any user interaction.

Vulnerability description

unrar 0.0.1 (aka unrar-free or unrar-gpl) suffers from a stack-based buffer over-read in unrarlib.c, related to ExtrFile and stricomp.

Severity breakdown

CVSS v3.1 9.1: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

• Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
• Attack complexity: Low. No special conditions; the attack can be repeated reliably.
• Privileges required: None. No account or prior access is needed.
• User interaction: None. No action from any user is needed.
• Scope: Unchanged. Impact stays within the vulnerable component.
• Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
• Integrity impact: None. No loss of integrity.
• Availability impact: High. Total loss of availability; the component can be shut down.

Underlying weakness

CWE-125: Out-of-bounds Read

The product reads data past the end, or before the beginning, of the intended buffer.

Affected products

• Rarlab Unrar: 0.0.1
• Debian Linux: 9.0

References

• http://www.openwall.com/lists/oss-security/2017/08/20/1
• https://bugs.debian.org/874060
• https://lists.debian.org/debian-lts-announce/2021/02/msg00026.html