What’s Vulnerable › Vulnerabilities

CVE-2026-61873: Grav before 9.1.8 Arbitrary File Write via Twig-Processed Filename

• Severity: high (CVSS 8.1 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-07-15 · updated 2026-10-24
• Weakness: CWE-73

Description

Grav before 9.1.8 contains an arbitrary file write vulnerability in the Form plugin's process.save.filename parameter, which is validated against path traversal before Twig processing but never re-validated after rendering. Attackers can submit form data containing path traversal sequences that are processed through Twig templates, allowing them to write arbitrary files including PHP webshells to the web root or other sensitive directories.

Affected products

• getgrav grav: before 9.1.8 — fixed in 9.1.8

How to fix

Upgrade to a fixed version: getgrav grav 9.1.8. Check the vendor advisory for mitigations.

References

• https://github.com/getgrav/grav/security/advisories/GHSA-q532-mvx7-42qg
• https://www.vulncheck.com/advisories/grav-before-arbitrary-file-write-via-twig-processed-filename
• https://github.com/getgrav/grav/security/advisories/GHSA-q532-mvx7-42qg

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