CVE-2025-53631: flaskblog XSS — Fix

Description

flaskBlog is a blog app built with Flask. In versions 2.8.1 and prior, improper sanitization of postContent when submitting POST requests to /createpost leads to arbitrary JavaScript execution (XSS) on all pages the post is reflected on including /, /post/[ID], /admin/posts, and /user/[ID] of the user that made the post. At time of publication, there are no public patches available.

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CVSS v3.1 Score

5.4

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

Weakness Type (CWE)

CWE-79 Cross-site Scripting (XSS)

Affected Products

Vendor	Product	Versions
dogukanurker	flaskblog	< 2.8.1

References

Advisories & Patches

https://github.com/DogukanUrker/flaskBlog/security/advisories/GHSA-cj43-h8qf-7rw7

Frequently Asked Questions

What is CVE-2025-53631? +

flaskBlog is a blog app built with Flask. In versions 2.8.1 and prior, improper sanitization of postContent when submitting POST requests to /createpost leads to arbitrary JavaScript execution (XSS) on all pages the post is reflected on including /, /post/[ID], /admin/posts, and /user/[ID] of the user that made the post. At time of publication, there are no public patches available. It has a CVSS v3.1 base score of 5.4 (MEDIUM).

How severe is CVE-2025-53631? +

CVE-2025-53631 has a CVSS v3.1 score of 5.4 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2025-53631? +

CVE-2025-53631 affects products from dogukanurker, specifically: flaskblog. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-53631? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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