CVE-2026-77939 (GCVE-0-2026-77939)

Vulnerability from cvelistv5 – Published: 2026-08-28 17:06 – Updated: 2026-08-29 11:47 X_Open Source
VLAI
Title
Flextype CMS 1.0.0-dev RCE via POST /api/v1/query Endpoint
Summary
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.
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-28 20:21 UTC
CWE
  • CWE-94 - Improper Control of Generation of Code ('Code Injection')
  • CWE-1336 - Improper Neutralization of Special Elements Used in a Template Engine
References
URL Tags
https://github.com/flextype/flextype/issues/595 technical-descriptionexploitissue-tracking
https://www.vulncheck.com/advisories/flextype-cms… third-party-advisory
Impacted products
Vendor Product Version CPE status
flextype flextype Affected: 0 , ≤ 1.0.0-dev (custom)
Affected: 0 , ≤ aea4ead8c449ea5517ed53b6dcbd28b0a528ad9d (git)
guessed Create a notification for this product.
Date Public
2026-08-28 00:00
Show details on NVD website

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

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