What’s Vulnerable › Vulnerabilities

CVE-2026-54002: Kirby: Cross-site scripting (XSS) from incomplete HTML/XML sanitization in `Dom::sanitize()`

• Severity: high (CVSS 8.5 v4.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-07-09 · updated 2026-10-25
• Weakness: CWE-79

Description

Kirby is an open-source content management system. Prior to 4.9.4 and 5.4.4, Kirby sites and plugins that use the writer or list fields or call Dom::sanitize(), Sane::sanitize(), Sane::Html::sanitize(), Sane::Svg::sanitize(), Sane::Xml::sanitize(), Sane::sanitizeFile(), or file sanitizeContents() with untrusted input allow malicious markup injected as children of an unknown HTML or XML tag to pass through Dom::sanitize() without being correctly sanitized, causing stored cross-site scripting. This issue is fixed in versions 4.9.4 and 5.4.4.

Affected products

• getkirby kirby: before 4.9.4; from 5.0.0, < 5.4.4

References

• https://github.com/getkirby/kirby/commit/0f0437b5128c910103cbc78fc34d94b2a3faef4c
• https://github.com/getkirby/kirby/commit/7ad76cf9c7387462828e6ebfc8404e31b37829e9
• https://github.com/getkirby/kirby/commit/9ec1873864441dbc06479ef7823da348ec7f2700
• https://github.com/getkirby/kirby/commit/bb2562e16c754493a403b8df84c9883108871e4c
• https://github.com/getkirby/kirby/releases/tag/4.9.4
• https://github.com/getkirby/kirby/releases/tag/5.4.4
• https://github.com/getkirby/kirby/security/advisories/GHSA-wr9h-4r83-f4v6

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