4.2Medium
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.
What this means for your business
- An attacker can use it only with access to the machine itself, with an administrator login, but only after tricking someone into an action such as opening a file or a link.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
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Scoring
- CVSS
- 4.2 (v3.1)
- Vector
CVSS:3.1/AV:L/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N- CVSS v4
- 2.4
- Weakness
- CWE-79
- Assigned by
- disclosure@vulncheck.com
Dates
- Published
- 2026-09-11
- Last modified
- 2026-09-11
- Sources
- NVD
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