Vulnerability · Published Jul 18, 2023 · Assigned by GitHub_M
CVE-2023-37897Server-side Template Injection (SSTI) in grav
High 7.2
In plain English
A high-severity injection in grav from getgrav. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 2.8% (higher than 87% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Grav is a file-based Web-platform built in PHP. Grav is subject to a server side template injection (SSTI) vulnerability. The fix for another SSTI vulnerability using `|map`, `|filter` and `|reduce` twigs implemented in the commit `71bbed1` introduces bypass of the denylist due to incorrect return value from `isDangerousFunction()`, which allows to execute the payload prepending double backslash (`\\`). The `isDangerousFunction()` check in version 1.7.42 and onwards retuns `false` value instead of `true` when the `\` symbol is found in the `$name`. This vulnerability can be exploited if the attacker has access to: 1. an Administrator account, or 2. a non-administrator, user account that has Admin panel access and Create/Update page permissions. A fix for this vulnerability has been introduced in commit `b4c6210` and is included in release version `1.7.42.2`. Users are advised to upgrade. There are no known workarounds for this vulnerability.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Packagist | getgrav/grav | 1.7.42.2 | GHSA-9436-3gmp-4f53 |
Affected products (as reported)
Weakness: CWE-74, CWE-393 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H