CVE-2023-34448 Grav Server-side Template Injection (SSTI) via Twig Default Filters

2023-06-1422:06:01

CWE-20

CWE-1336

GitHub_M

www.cve.org

grav

flat-file

ssti

vulnerability

patch

twig

remote code execution

8.8 High

CVSS3

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

HIGH

Integrity Impact

HIGH

Availability Impact

HIGH

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

8.3 High

AI Score

Confidence

High

0.008 Low

EPSS

Percentile

81.6%

JSON

Grav is a flat-file content management system. Prior to version 1.7.42, the patch for CVE-2022-2073, a server-side template injection vulnerability in Grav leveraging the default filter() function, did not block other built-in functions exposed by Twig’s Core Extension that could be used to invoke arbitrary unsafe functions, thereby allowing for remote code execution. A patch in version 1.74.2 overrides the built-in Twig map() and reduce() filter functions in system/src/Grav/Common/Twig/Extension/GravExtension.php to validate the argument passed to the filter in $arrow.

CNA Affected

[
  {
    "vendor": "getgrav",
    "product": "grav",
    "versions": [
      {
        "version": "< 1.7.42",
        "status": "affected"
      }
    ]
  }
]