XSS in Dogukanurker Flaskblog
CVE-2025-55735
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.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.
EPSS exploit prediction
EPSS: 0.002 (10.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 10th percentile — 10.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000
Affected products
- Dogukanurker Flaskblog — versions <= 2.8.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/DogukanUrker/FlaskBlog/security/advisories/GHSA-gj9v-qhc3-gcfx (Exploit, Third Party Advisory)
Frequently asked questions
- What is CVE-2025-55735?
- CVE-2025-55735 is a medium-severity vulnerability in Dogukanurker Flaskblog, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2025-08-19.
- How severe is CVE-2025-55735?
- Medium severity. CVSS v3 base score is 5.4 out of 10.
- Is CVE-2025-55735 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.