CVE-2026-61873 (GCVE-0-2026-61873)

Vulnerability from cvelistv5 – Published: 2026-07-15 11:25 – Updated: 2026-07-15 11:47
VLAI
Title
Grav before 9.1.8 Arbitrary File Write via Twig-Processed Filename
Summary
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.
Severity
7.2 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N
8.1 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
CWE
  • CWE-73 - External Control of File Name or Path
Assigner
References
Impacted products
Vendor Product Version
getgrav grav Affected: 0 , < 9.1.8 (semver)
Unaffected: 9.1.8 (semver)
Create a notification for this product.
Date Public
2026-06-26 00:00
Credits
alienkeric
Show details on NVD website
To clipboard 

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          "name": "GitHub Security Advisory (GHSA-q532-mvx7-42qg)",
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    "datePublished": "2026-07-15T11:25:56.100Z",
    "dateReserved": "2026-07-10T21:54:26.760Z",
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    "state": "PUBLISHED"
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  }
}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.