Remote code execution in Backdrop Archive_Tar pear library

1) Link following

EUVDB-ID: #VU55101

Risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2021-32610

CWE-ID: CWE-59 - Improper Link Resolution Before File Access ('Link Following')

Exploit availability: No

Description

The vulnerability allows a remote attacker to compromise the affected system.

The vulnerability exists due to the application does not check if the file in the archive is a symbolic link when extracting it. A remote attacker can pass a specially crafted file to the application and overwrite arbitrary files on the system. Successful exploitation of the vulnerability may allow an attacker to compromise the affected system.

Mitigation

Install update from vendor's website.

Vulnerable software versions

Backdrop CMS: 1.0.0 - 1.19.1

CPE2.3

• cpe:2.3:a:backdropcms:backdrop:1.0.6:*:*:*:*:*:*:*
• cpe:2.3:a:backdropcms:backdrop:1.19.1:*:*:*:*:*:*:*
• cpe:2.3:a:backdropcms:backdrop:1.2.4:*:*:*:*:*:*:*
• cpe:2.3:a:backdropcms:backdrop:1.3.7:*:*:*:*:*:*:*
• cpe:2.3:a:backdropcms:backdrop:1.4.5:*:*:*:*:*:*:*
• cpe:2.3:a:backdropcms:backdrop:1.5.3:*:*:*:*:*:*:*
• cpe:2.3:a:backdropcms:backdrop:1.6.4:*:*:*:*:*:*:*
• cpe:2.3:a:backdropcms:backdrop:1.7.4:*:*:*:*:*:*:*
• cpe:2.3:a:backdropcms:backdrop:1.8.4:*:*:*:*:*:*:*
• cpe:2.3:a:backdropcms:backdrop:1.9.6:*:*:*:*:*:*:*

External links

https://backdropcms.org/security/backdrop-sa-core-2021-004

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.