dbcve.org
Code InjectionWeakness · CWE-94

CVE-2026-58655

HIGH · 8.8 CVSS v3.1 Published 2026-07-15
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
94/100
Remediation priority · Urgent
Remotely reachable Zero-click 5 weeks old

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Stored server-side template injection in Grav Flex Objects plugin where user-controlled frontmatter (page.header.flex.collection.title or page.header.flex.object.title) is passed to Twig's template_from_string(), bypassing Security::cleanDangerousTwig() sanitization. This allows arbitrary Twig code execution, which can escalate to RCE through Grav's internal services.

MitigationUpgrade getgrav/grav-plugin-flex-objects to version 1.4.0 or later. If upgrade is not immediately possible, restrict public access to Flex Objects pages or disable the plugin until patched.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check Flex Objects plugin version
    Locate the plugin directory (typically /user/plugins/flex-objects or within vendor/getgrav) and read the plugin's yaml or json version file. Compare the version number to 1.4.0.
    Affected if The installed version is lower than 1.4.0
  2. Verify plugin is enabled
    Check the plugin configuration file (flex-objects.yaml in /user/config/plugins/) or the plugin's enabled status in Grav's admin panel.
    Affected if The Flex Objects plugin is installed and enabled
  3. Identify pages using Flex Objects frontmatter
    Search content directories (typically /user/pages/) for markdown files containing 'flex:' or 'flex.collection' or 'flex.object' in their YAML frontmatter between the --- delimiters.
    Affected if Any content files contain flex collection or object definitions in frontmatter
  4. Inspect dangerous frontmatter fields
    For each page with flex configuration, examine the frontmatter for page.header.flex.collection.title or page.header.flex.object.title fields and verify whether they contain Twig template syntax ({{, {%, or other template delimiters).
    Affected if The frontmatter contains page.header.flex.collection.title or page.header.flex.object.title with unescaped Twig template syntax or suspicious content
  5. Check for existing template injection artifacts
    Review the compiled cache (if accessible) or look for unexpected files/modifications in the system that may indicate prior exploitation of this SSTI vulnerability.
    Affected if Unexplained Twig template code is found in cached output or system behavior suggests code execution occurred

A user is affected if they have Flex Objects plugin enabled with version lower than 1.4.0 AND have content pages with flex collection or object definitions in frontmatter that could contain malicious Twig code.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Upgrade getgrav/grav-plugin-flex-objects to version 1.4.0 or later. If upgrade is not immediately possible, restrict public access to Flex Objects pages or disable the plugin until patched.

Recommended fix High confidence

Upgrade getgrav/grav-plugin-flex-objects to version 1.4.0 or later

  1. 1. Identify the Grav installation and locate the Flex Objects plugin in the `user/plugins/` directory or via Composer.
  2. 2. Check the current version of the getgrav/grav-plugin-flex-objects plugin by inspecting the plugin's `blueprints.yaml` or `flex-objects.php` version constant, or by running `bin/gpm list -i` if available.
  3. 3. If the installed version is before 1.4.0, upgrade the plugin using one of these methods: a) Run `bin/gpm update flex-objects` from the Grav root directory, or b) Update via Composer with `composer update getgrav/grav-plugin-flex-objects`, or c) Manually download version 1.4.0 or later from the Grav plugin repository and replace the plugin files.
  4. 4. After upgrading, verify the new version is installed by running `bin/gpm list -i` or checking the plugin's version file.
  5. 5. Test that the Flex Objects functionality works correctly and that the vulnerability is remediated by confirming that arbitrary Twig code in title frontmatter is no longer executed.
Caveat Review plugin changelog for any breaking changes between your current version and 1.4.0; minor version upgrades typically maintain backward compatibility but custom Flex Object configurations should be tested

Generated from the published advisory — verify against the referenced sources before acting.

Have this fixed Scoped from the published advisory
  • Consultation3.0 h
  • Implementation2.0 h
  • Testing4.0 h
  • Review / QA2.0 h
11.0 hours of engineering $1,920
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-58655 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
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