Machine-written summary
Summary written by Claude Haiku from the source advisory. Not reviewed by a person.
The Grav CMS (getgrav/grav, Packagist) is affected in versions before 1.8.0-beta.27. A server-side template injection flaw in the Twig sanitization method cleanDangerousTwig lets an authenticated user with editor permissions run arbitrary commands on the server through a form's process section, and the advisory says an unauthenticated visitor may also be able to exploit it when an existing form passes user input through evaluate_twig. Upgrade to 1.8.0-beta.27 or later, which is listed as the fixed version.
Not analysed yet
We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.
Severity and exploitation
| Score | Rating | CVSS | Vector | Source |
|---|---|---|---|---|
| 8.7 | High | 4.0 | CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N | CNA (GitHub_M) |
- CISA KEV Not listed.
- EPSS 0.030, the 87th percentile, on 15 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.
Timeline
- 31 Oct 2026, 14:03 UTC First seen by agentprime
- 31 Oct 2026, 14:03 UTC Confirmed by OSV