CVE-2021-29440

Name: CVE-2021-29440
Creator: NVD / NIST
Published: 2021-04-13T20:15:22.36+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.2/10EPSS 30.62%

Last modified Jun 17, 2026

CVE-2021-29440 is a high-severity vulnerability rated 7.2/10 on the CVSS scale. 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. EPSS estimates a 30.62% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

7.2/10

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

EPSS Probability

30.62%

98.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-94

Affected Software

Vendor	Product	Versions
Getgrav	Grav	< 1.7.11

References

http://packetstormsecurity.com/files/162987/Grav-CMS-1.7.10-Server-Side-Template-Injection.htmlExploit, Third Party Advisory, VDB Entry
https://blog.sonarsource.com/grav-cms-code-execution-vulnerabilitiesExploit, Third Party Advisory
https://github.com/getgrav/grav/security/advisories/GHSA-g8r4-p96j-xfxcThird Party Advisory
https://packagist.org/packages/getgrav/gravProduct, Third Party Advisory
http://packetstormsecurity.com/files/162987/Grav-CMS-1.7.10-Server-Side-Template-Injection.htmlExploit, Third Party Advisory, VDB Entry
https://blog.sonarsource.com/grav-cms-code-execution-vulnerabilitiesExploit, Third Party Advisory
https://github.com/getgrav/grav/security/advisories/GHSA-g8r4-p96j-xfxcThird Party Advisory
https://packagist.org/packages/getgrav/gravProduct, Third Party Advisory

Timeline

Published: Apr 13, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-29440?

How severe is CVE-2021-29440?

CVE-2021-29440 has a CVSS score of 7.2/10 (HIGH severity). The EPSS model estimates a 30.62% probability of exploitation in the next 30 days.

How do I fix CVE-2021-29440?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-29440?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST