Interpretation Conflict Affecting symfony/html-sanitizer package, versions <6.4.40>=7.0.0-BETA1, <7.4.12>=8.0.0-BETA1, <8.0.12
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-PHP-SYMFONYHTMLSANITIZER-16873894
- published24 May 2026
- disclosed20 May 2026
- creditClaude Mythos
Introduced: 20 May 2026
CVE-2026-45066 (opens in a new tab)How to fix?
Upgrade symfony/html-sanitizer to version 6.4.40, 7.4.12, 8.0.12 or higher.
Overview
symfony/html-sanitizer is a Provides an object-oriented API to sanitize untrusted HTML input for safe insertion into a document's DOM.
Affected versions of this package are vulnerable to Interpretation Conflict via URL parsing and policy enforcement in UrlSanitizer/UrlAttributeSanitizer. An attacker can bypass configured link or media host/scheme allowlists by supplying crafted URLs that are interpreted differently by Symfony’s RFC-3986-style parser and browsers’ WHATWG URL handling, or by using <area href> elements that are checked against the wrong policy. This allows off-allowlist destinations to survive sanitization and be rendered as trusted links or media URLs.