Red Hat RESTEasy SourceProvider SourceProvider.writeTo xml external entity reference

Summaryinfo

A vulnerability identified as critical has been detected in Red Hat RESTEasy. Affected is the function SourceProvider.writeTo of the component SourceProvider. The manipulation leads to xml external entity reference. This vulnerability is referenced as CVE-2026-17615. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability was found in Red Hat RESTEasy (affected version not known). It has been rated as critical. This issue affects the function SourceProvider.writeTo of the component SourceProvider. The manipulation with an unknown input leads to a xml external entity reference vulnerability. Using CWE to declare the problem leads to CWE-611. The product processes an XML document that can contain XML entities with URIs that resolve to documents outside of the intended sphere of control, causing the product to embed incorrect documents into its output. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

A flaw was found in RESTEasy's SourceProvider. This vulnerability allows an unauthenticated attacker to perform an unauthenticated remote file read. By sending a specially crafted XML body with a DOCTYPE declaration referencing external entities to an endpoint that accepts application/xml and returns Source or StreamSource, the server can be tricked into resolving the entity and including sensitive file contents in the HTTP response. This is due to the SourceProvider.writeTo() method creating a SAXParser without disabling external entity resolution, leading to an XML External Entity (XXE) vulnerability.

The advisory is shared at access.redhat.com. The identification of this vulnerability is CVE-2026-17615 since 07/27/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details are known, but no exploit is available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 08/31/2026).

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

• Red Hat

Name

• RESTEasy

License

• open-source

Website

• Vendor: https://www.redhat.com/

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

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