CVE-2026-73634 Apache Struts: Unbounded read of a Content Security Policy violation report
Attackers can exhaust server memory via unbounded CSP report submissions, causing denial of service in Apache Struts applications with this feature enabled.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-73634?
CVE-2026-73634 is a high-severity denial of service vulnerability in Apache Struts, published on 15 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Uncontrolled resource consumption vulnerability in Apache Struts. An application that exposes an endpoint collecting Content Security Policy violation reports reads the submitted report into memory without bounding how much it will accept, so a single request can exhaust the heap and deny service to other users. Such endpoints are ordinarily reachable without authentication. The core distribution maps no such endpoint by default; applications that do not collect violation reports are not affected.
This issue affects Apache Struts: from 6.0.0 through 6.10.0, from 7.0.0 through 7.2.1.
Users are recommended to upgrade to version 6.11.0 or 7.3.0, which fixes the issue.
Weakness: CWE-400
Which versions are affected by CVE-2026-73634?
It affects 1 product.
Products include Apache Struts.
How do I fix CVE-2026-73634?
No fix has been published for CVE-2026-73634 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-73634 being exploited?
There is no known exploitation of CVE-2026-73634 in the wild and no public exploit code.
Other vulnerabilities in Apache Struts
Sources
Also known as GHSA-wxrh-8hrv-h99q.