usefathom Fathom up to 1.3.1 Analytics Collection Endpoint parseHostname/parsePathname hostname/pathname cross site scripting

Summaryinfo

A vulnerability, which was classified as problematic, has been found in usefathom Fathom up to 1.3.1. Impacted is the function parseHostname/parsePathname of the component Analytics Collection Endpoint. Performing a manipulation of the argument hostname/pathname results in cross site scripting. This vulnerability only affects products that are no longer supported by the maintainer. This vulnerability is identified as CVE-2026-65697. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability classified as problematic has been found in usefathom Fathom up to 1.3.1. This affects the function parseHostname/parsePathname of the component Analytics Collection Endpoint. The manipulation of the argument hostname/pathname with an unknown input leads to a cross site scripting vulnerability. CWE is classifying the issue as CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. This is going to have an impact on integrity. The summary by CVE is:

Fathom Lite through 1.3.1 contains a stored cross-site scripting vulnerability in the analytics collection endpoint that allows unauthenticated attackers to inject a javascript: URI into the Top Pages dashboard by supplying a crafted hostname and pathname to the unauthenticated /collect endpoint. The parseHostname and parsePathname functions perform no URI scheme validation, allowing a javascript: hostname combined with a newline-prefixed pathname to be stored and later rendered as an anchor href in the authenticated dashboard without sanitization, enabling session hijacking and full account takeover when an operator clicks the poisoned entry.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-65697 since 07/22/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

• usefathom

Name

• Fathom

Version

• 1.3.0
• 1.3.1

Support

• end of life

CPE 2.3info

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• 🔒

CPE 2.2info

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• 🔒

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Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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