Flextype CMS through v1.0.0-dev contains an expression language injection vulnerability that allows authenticated attackers with a valid API token… (CVE-2026-77939)
Flextype CMS through v1.0.0-dev contains an expression language injection vulnerability that allows authenticated attackers with a valid API token to read arbitrary files by passing unsanitized user-supplied input to the Symfony ExpressionLanguage engine via the POST /api/v1/query endpoint. Attackers can leverage exposed application objects including filesystem() and serializers() within the evaluation scope to read arbitrary server files and achieve conditional remote code execution if a PHP file can be placed on disk through a secondary vector.
Flextype CMS through v1.0.0-dev contains an expression language injection vulnerability that allows authenticated attackers with a valid API token… (CVE-2026-77939)
Description
Flextype CMS through v1.0.0-dev contains an expression language injection vulnerability that allows authenticated attackers with a valid API token to read arbitrary files by passing unsanitized user-supplied input to the Symfony ExpressionLanguage engine via the POST /api/v1/query endpoint. Attackers can leverage exposed application objects including filesystem() and serializers() within the evaluation scope to read arbitrary server files and achieve conditional remote code execution if a PHP file can be placed on disk through a secondary vector.
CVSS v3.1
Score 6.5medium
Weaknesses
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-j8rr-2wmh-q2h8
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-77939"]
- Ecosystems
- []
- Database Specific Severity
- HIGH
- Cvss Version
- 3.1
Threat ID: 6a92f7edacd9273b49e75f92
Added to database: 08/29/2026, 15:17:01 UTC
Last updated: 08/29/2026, 15:17:15 UTC
Views: 1
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