CVE-2026-77939

EUVD-2026-67837

28.08.2026, 20:19

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.

Code Injection

Provider	Type	Base Score	Atk. Vector	Atk. Complexity	Priv. Required	Vector
NIST	Primary	6.5 MEDIUM	NETWORK	LOW	LOW	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Awaiting analysis

This vulnerability is currently awaiting analysis.

Base Score

CVSS 3.x

EPSS Score

Percentile: 36.92%

Common Weakness Enumeration

CWE-94 - Improper Control of Generation of Code ('Code Injection')
The software constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.

References

https://github.com/flextype/flextype/issues/595

https://www.vulncheck.com/advisories/flextype-cms-dev-rce-via-post-api-v1-query-endpoint