CVE-2025-55735 (GCVE-0-2025-55735)

Vulnerability from cvelistv5 – Published: 2025-08-19 18:56 – Updated: 2025-08-19 19:18
VLAI
Title
flaskBlog Stored XSS Vulnerability
Summary
flaskBlog is a blog app built with Flask. In 2.8.0 and earlier, when creating a post, there's no validation of the content of the post stored in the variable "postContent". The vulnerability arises when displaying the content of the post using the | safe filter, that tells the engine to not escape the rendered content. This can lead to a stored XSS inside the content of the post. The code that causes the problem is in template/routes.html.
Severity
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-08-19 19:16 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
  • CWE-807 - Reliance on Untrusted Inputs in a Security Decision
Assigner
GitHub_M CNA
References
Impacted products
Vendor Product Version
DogukanUrker FlaskBlog Affected: <= 2.8.0
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