#VU77509 Input validation error in Grav CMS - CVE-2023-34448

Vulnerability identifier: #VU77509

Vulnerability risk: Low

CVSSv4.0: 6.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2023-34448

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Grav CMS
Web applications / CMS

Vendor: Grav CMS

Description

The vulnerability allows a remote user to execute arbitrary code on the target system.

The vulnerability exists due to Server-side Template Injection (SSTI) issue in the Twig Default Filters. A remote administrator can pass specially crafted input to the application and execute arbitrary code on the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Grav CMS: 1.7.0 - 1.7.40

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External links
https://github.com/twigphp/Twig/blob/v1.44.7/src/Environment.php#L148
https://github.com/getgrav/grav/security/advisories/GHSA-whr7-m3f8-mpm8
https://www.github.com/getgrav/grav/commit/9d6a2dba09fd4e56f5cdfb9a399caea355bfeb83
https://github.com/getgrav/grav/commit/8c2c1cb72611a399f13423fc6d0e1d998c03e5c8
https://huntr.dev/bounties/3ef640e6-9e25-4ecb-8ec1-64311d63fe66/

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated privileged user via the Internet.

Is there known malware, which exploits this vulnerability?

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