XSS in Kepano Defuddle
CVE-2026-30830
Defuddle cleans up HTML pages. Prior to version 0.9.0, the _findContentBySchemaText method in src/defuddle.ts interpolates image src and alt attributes directly into an HTML string without escaping. An attacker can use a " in the alt attribute to break out of the attribute context and inject event handler. This issue has been patched in version 0.9.0.
Vulnerability class: XSS (Cross-Site Scripting)
EPSS: 0.003 (17.0th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
Affected products
- Kepano Defuddle — versions < 0.9.0
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Mitigation, Vendor Advisory)
- security-advisories@github.com (Patch, x_refsource_MISC)
Frequently asked questions
- What is CVE-2026-30830?
- CVE-2026-30830 is a medium-severity vulnerability in Kepano Defuddle, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2026-03-07.
- How severe is CVE-2026-30830?
- Medium severity. CVSS v3 base score is 6.1 out of 10.