Description
jsoup is a Java library for working with real-world HTML. From 1.14.3 until 1.23.1, jsoup's HTML parser could incorrectly handle a malformed tag name ending in a control character, causing the tag to acquire the parsing behavior of a different element. When a custom Safelist permits certain raw-text elements, this misparsing can cause content that should remain inert text to be emitted as active markup after serialization, potentially resulting in cross-site scripting. jsoup's built-in Safelists are not affected. This issue is fixed in version 1.23.1.
References4
Metrics
- CVSS 3.1
-
4.7
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 22 · as of 12 November 2026
- CWE
- CWE-79
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