How severe is CVE-2021-29440?

CVE-2021-29440 has a CVSS 3.x base score of 8.4, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-29440 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 31% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-29440?

CVE-2021-29440 affects Getgrav Grav. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-29440?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-29440 published?

CVE-2021-29440 was published on 2021-04-13 and last updated on 2026-06-17.

CVE-2021-29440

CVE-2021-29440 is a high-severity vulnerability in Getgrav Grav with a CVSS 3.x base score of 8.4. Its EPSS exploit-prediction score of 31% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-94.

Key facts

Severity: High (CVSS 3.x base score 8.4)
CVSS v2: 6.5
EPSS exploit prediction: 31% (98th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-94
Affected product: Getgrav Grav
Published: 2021-04-13
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2021-29440?: 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.
How severe is CVE-2021-29440?: CVE-2021-29440 has a CVSS 3.x base score of 8.4, rated high severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-29440 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 31% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-29440?: CVE-2021-29440 affects Getgrav Grav. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-29440?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-29440 published?: CVE-2021-29440 was published on 2021-04-13 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:getgrav:grav:*:*:*:*:*:*:*:*

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