8.6

CVE-2025-66021: owasp java_html_sanitizer Cross-site Scripting

CVSS: 8.6v4.0HighAnalyzed
AliasesCGA-45f8-2cf8-g6x8CGA-cmcc-hqmr-2w58CGA-4j22-r37q-254r
Published 26-11-2025Last modified 26-11-2025
Open JSON

Vulnerability summary

CVE-2025-66021 is a high (CVSS 8.6) Cross-site Scripting vulnerability in owasp java_html_sanitizer. EPSS estimates a 0.25% chance of exploitation in the next 30 days, higher than 15.1% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
44/100
0100
Medium · default modelHow is this calculated?
CVSS score
8.6/10
010
High · v4.0 (CVE.org)
EPSS score
0.25%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1github

Advisory lineage

Upstream 0 · Downstream 0 · Related 1
CGA-367H-P22W-H45X

Timeline

  1. 26-11-2025
    PublishedVulnerability first disclosed.
  2. 26-11-2025
    Last modifiedVulnerability information updated.

Description

OWASP Java HTML Sanitizer is a configureable HTML Sanitizer written in Java, allowing inclusion of HTML authored by third-parties in web applications while protecting against XSS. In version 20240325.1, OWASP java html sanitizer is vulnerable to XSS if HtmlPolicyBuilder allows noscript and style tags with allowTextIn inside the style tag. This could lead to XSS if the payload is crafted in such a way that it does not sanitise the CSS and allows tags which is not mentioned in HTML policy. At time of publication no known patch is available.

CVSS metrics

6 scores · 5 sources · 2 versions

EPSS trend

Probability

0.25%

Chance of exploitation in the next 30 days

Percentile

15%

Versus all other CVEs

30-day change

0.00 pp

From 0.25% on 18-09-2026

18-09-202618-10-2026
EPSS score
0.25%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • githubUnverified

    Java Html Sanitizer

    Maturity: poc

Weaknesses

CWE · root cause

Affected systems

Chainguard7 products
  • keycloak-26.2All versions (No fix recorded)
  • keycloak-26.2-iamguarded-compatAll versions (No fix recorded)
  • keycloak-26.4< 26.4.7-r3
  • keycloak-fips-26.2-iamguarded-fipsAll versions (No fix recorded)
  • keycloak-fips-26.3-iamguarded-fipsAll versions (No fix recorded)
Owasp2 products
Com.googlecode.owasp-java-html-sanitizer1 product
  • owasp-java-html-sanitizer≥ 20240325.1, < 20260101.1
Wolfi1 product
  • keycloak-26.4< 26.4.7-r3

4 vendors · 11 products

References

8 links