CVE-2026-89145

Flextype CMS versions 0.9.9 through 1.0.0-alpha.3 fail to HTML-escape plugin directory names in the dependency error page rendered by getValidPluginsDependencies(). Attackers with write access to the plugins directory can create a plugin with HTML characters in its name to execute arbitrary scripts in users' browsers when dependency validation fails.

Score

CVSS 3.1 4.2 Medium

Status

Deferred - disclosure@vulncheck.com

Published

2026-09-11

Last modified

2026-09-11

Weaknesses

CWE-79

Affected products

• Flextype (Flextype)

References

• https://github.com/flextype/flextype
• https://github.com/flextype/flextype/blob/aea4ead8c449ea5517ed53b6dcbd28b0a528ad9d/src/flextype/core/Plugins.php#L345
• https://github.com/flextype/flextype/issues/597
• https://www.vulncheck.com/advisories/flextype-cms-0.9.9-through-1.0.0-alpha.3-stored-xss-via-plugin-directory