CVE-2021-29440

Public Exploit
Twig allowing dangerous PHP functions by default

Description

Grav is a file based Web-platform. Twig processing of static pages can be enabled in the front matter by any administrative user allowed to create or edit pages. As the Twig processor runs unsandboxed, this behavior can be used to gain arbitrary code execution and elevate privileges on the instance. The issue was addressed in version 1.7.11.

Category

8.4
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 9.77% Top 10%
Third-Party Advisory packetstormsecurity.com Third-Party Advisory sonarsource.com Third-Party Advisory github.com Third-Party Advisory packagist.org
Affected: getgrav grav
Published at:
Updated at:

References

Link Tags
https://github.com/getgrav/grav/security/advisories/GHSA-g8r4-p96j-xfxc third party advisory
https://packagist.org/packages/getgrav/grav product third party advisory
http://packetstormsecurity.com/files/162987/Grav-CMS-1.7.10-Server-Side-Template-Injection.html third party advisory vdb entry exploit
https://blog.sonarsource.com/grav-cms-code-execution-vulnerabilities third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2021-29440?
CVE-2021-29440 has been scored as a high severity vulnerability.
How to fix CVE-2021-29440?
To fix CVE-2021-29440, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-29440 being actively exploited in the wild?
It is possible that CVE-2021-29440 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~10% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-29440?
CVE-2021-29440 affects getgrav grav.
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