Is CVE-2026-120971 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-120971 being exploited in the wild.

How severe is CVE-2026-120971?

Medium severity, with a CVSS score of 5.3, published 3 November 2026.

Which products and versions are affected?

Red Hat RESTEasy 7.0.2.Final and possibly other versions.

Is there a fix for CVE-2026-120971?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-120971 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-120971?

Check whether you run Red Hat RESTEasy at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-120971: RESTEasy default exception mapper information disclosure

CVE-2026-120971 · Severity: medium · CVSS 5.3 · Published 2026-11-03

RESTEasy is a Java framework for building REST web services. When an unhandled exception occurs and no custom exception handler is configured, the framework returns the exception's localized message in the HTTP 500 response body, potentially exposing sensitive information to unauthenticated remote clients. An attacker can trigger such exceptions to extract system details.

Technologies: Red Hat RESTEasy. Vendors: Red Hat.

Quick answers

Is CVE-2026-120971 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-120971 being exploited in the wild.
How severe is CVE-2026-120971?: Medium severity, with a CVSS score of 5.3, published 3 November 2026.
Which products and versions are affected?: Red Hat RESTEasy 7.0.2.Final and possibly other versions.
Is there a fix for CVE-2026-120971?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-120971 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-120971?: Check whether you run Red Hat RESTEasy at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The default exception mapper in RESTEasy fails to sanitize exception messages in HTTP 500 responses when no application-specific exception mapper handles the error. An unauthenticated remote attacker with network access can trigger unhandled exceptions (other than WebApplicationException) via crafted requests, causing sensitive exception details to be disclosed in the response body. The vulnerability is confirmed in RESTEasy 7.0.2.Final; affected and fixed version ranges require confirmation.

Affected products

Red Hat RESTEasy 7.0.2.Final and possibly other versions

Timeline

2026-11-03: disclosed

References

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