VulnerabilityAnalyzed
CVE-2026-27645
Since Flask returns text/html by default for plain string responses, the browser parses and executes injected JavaScript.
MEDIUM 6.1EPSS 0.45%
Does this matter?
Lower severity and a low EPSS score (0.45%). Track it; it rarely justifies an emergency change on its own.
Description
changedetection.io is a free open source web page change detection tool. In versions prior to 0.54.1, the RSS single-watch endpoint reflects the UUID path parameter directly in the HTTP response body without HTML escaping. Since Flask returns text/html by default for plain string responses, the browser parses and executes injected JavaScript. Version 0.54.1 contains a fix for the issue.
- CVSS 3.1
- 6.1 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
- EPSS
- 0.45% probability · 38th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-79
- Affected
- webtechnologies/changedetection
- Source
- security-advisories@github.com
References
- https://github.com/dgtlmoon/changedetection.io/commit/a385c89abf44b52fcfa20c7c6a6dd3047c4c1eb5Patch
- https://github.com/dgtlmoon/changedetection.io/security/advisories/GHSA-mw8m-398g-h89wExploit, Vendor Advisory
- https://github.com/dgtlmoon/changedetection.io/security/advisories/GHSA-mw8m-398g-h89wExploit, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.