CVE-2026-73634
CVE-2026-73634 — Apache Struts: Unbounded read of a Content Security Policy violation report
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.
Published Updated Sources: NVD, Apache Software Foundation (CNA), GitHub, GitHub Security Advisory, SOCRadar CTI
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the scoring sources call it.
Exploitation
Unreported
no source claims exploitation
EPSS
0%
ahead of 0% of scored CVEs
CVSS base
Unscored
no source published a base score
Remediation
The vendor's own words where we have them.
Upgrade Apache Struts to a fixed release. Apply vendor patches per advisory and restrict external exposure of the affected component until patched.
First 24 hours
Ordered from the record's own fields — exposure first, because you cannot patch what you have not found.
- Identify exposed assets running affected vendor/product/version combinations.
- Prioritize based on EPSS, PoC availability, and external exposure.
- Search available logs for exploit probes, errors, authentication anomalies, or suspicious child processes matching the vulnerability class.
Affected scope
Vendor, product and version as the advisories word them.
| Vendor | Product | Versions | Status |
|---|---|---|---|
| Apache | Apache Struts | 6.0.0 to <= 6.10.0 | Vulnerable |
| Apache | Apache Struts | 7.0.0 to <= 7.2.1 | Vulnerable |
What this weakness leads to
MITRE's own consequences and mitigations for the weakness class — the authority's wording, not guidance derived from the CVSS vector.
CWE-400 · Uncontrolled Resource Consumption
- DoS: Crash, Exit, or Restart
- DoS: Resource Consumption (CPU)
- DoS: Resource Consumption (Memory)
- DoS: Resource Consumption (Other)
Mitigation: Design throttling mechanisms into the system architecture. The best protection is to limit the amount of resources that an unauthorized user can cause to be expended. A strong authentication and access control model will help prevent such attacks from occurring in the first place. The login application should be protected against DoS attacks as much as possible. Limiting the database access, perhaps by caching result sets, can help minimize the resources expended. To further limit the potential for a DoS attack, consider tracking the rate of requests received from users and blocking requests that exceed a defined rate threshold.
Weakness & attack patterns
- CWE-400Uncontrolled Resource Consumption
Attack patterns reported against this CVE. The ATT&CK techniques below are inferred from its weakness class.
- T1499Endpoint Denial of Service
Detection
Read off the CVSS vector and the weakness class. Starting points, not rules we have tested.
Timeline
What happened to this CVE, newest first — with the readings a source repeats on a schedule counted underneath rather than listed.
- 2026
Initial · CVE published
Aug 15, 2026 · NVD
Added · GHSA-wxrh-8hrv-h99q published (unknown)
Aug 15, 2026 · GitHub Security Advisory
Source activity
Readings a source repeats on a schedule, counted rather than listed.
- 1×CVE modified by NIST, Modified, LinkAug 15, 2026 · SOCRadar CTI
References
3 on the record
- cwiki.apache.org/confluence/display/WW/S2-073
Vendor Advisory, NIST
- nvd.nist.gov/vuln/detail/CVE-2026-73634
NVD
- github.com/advisories/GHSA-wxrh-8hrv-h99q
Exploit, Third Party Advisory
Elsewhere on this site
- Apacheevery CVE for this vendor
- Remote Code Execsame class
- CWE-400other pages naming this weakness
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record1
What should defenders know first?
CVE-2026-73634 is Apache Struts: Unbounded read of a Content Security Policy violation report, a unscored vulnerability affecting Apache Struts from Apache Software Foundation. The current evidence does not list it in CISA KEV, and the exploit status is: Active exploitation is not confirmed from current sources for CVE-2026-73634. Public exploit evidence is: A public PoC is not confirmed from current sources for CVE-2026-73634. The affected-version evidence is listed in the key facts and affected products tables. Defenders should first verify whether exposed or business-critical assets run those versions, then apply vendor patches or mitigations, restrict reachable attack surface, and preserve logs for detection review. CVSS null describes technical severity, while EPSS 0% helps estimate near-term exploit likelihood; neither replaces asset context. Unknown fields should remain explicit in tickets, and threat actor, IOC, victimology, or payload claims should not be added unless a cited source supports them. Monitor CISA KEV, vendor advisories, NVD changes, public PoC repositories, and internal telemetry for update triggers.