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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/flextype/flextype/issues/595
https://www.vulncheck.com/advisories/flextype-cms-dev-rce-via-post-api-v1-query-endpoint

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-28 20:19

Updated : 2026-09-08 20:23

NVD link : CVE-2026-77939

Mitre link : CVE-2026-77939

CVE.ORG link : CVE-2026-77939

JSON object : View

Products Affected

No product.

CWE

CWE-94

Improper Control of Generation of Code ('Code Injection')

CWE-1336

Improper Neutralization of Special Elements Used in a Template Engine

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