CVE-2026-58655
HIGH Exploitation: PoC
8.8
CVSS 3.1
Description
The bundled Grav Flex Objects plugin (getgrav/grav-plugin-flex-objects) before 1.4.0 contains a stored server-side template injection vulnerability. When rendering dynamic collection or object titles, the plugin passes user-controlled frontmatter values (page.header.flex.collection.title or page.header.flex.object.title) to Twig's template_from_string(), causing them to be evaluated as Twig code rather than treated as text. This path bypasses Grav's Security::cleanDangerousTwig() sanitization. An attacker who can control the title frontmatter of a publicly reachable Flex Objects page can achieve arbitrary Twig execution and escalate to remote command execution via access to internal Grav services such as the scheduler.
Metadata
Severity & Metrics
8.8
HIGH CVSS 3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC — CISA Coordinator
Affected products (1)
| Vendor | Product | Platform | Versions |
|---|---|---|---|
| getgrav | grav | — | 0 < 1.4.0, 1.4.0 |
Weakness (CWE)
| CWE | Source | Description |
|---|---|---|
| CWE-94 | cna | Improper Control of Generation of Code ('Code Injection') |
CVSS scores (2)
| Score | Severity | Version | Source | Vector |
|---|---|---|---|---|
| 8.8 | HIGH | 3.1 | cna | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| 8.7 | HIGH | 4.0 | cna | 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 |
References (2)
- GitHub Security Advisory (GHSA-623v-m3c4-3pw8) https://github.com/getgrav/grav/security/advisories/GHSA-623v-m3c4-3pw8
- VulnCheck Advisory: Grav Flex Objects - Server-Side Template Injection via Dynamic Titles https://www.vulncheck.com/advisories/grav-flex-objects-server-side-template-injection-via-dynamic-titles