Cyber Resilience

CVE-2025-31650

High

Published: 28 April 2025

Published
28 April 2025
Modified
03 November 2025
KEV Added
Patch
CVSS Score v3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.2025 95.7th percentile
Risk Priority 27 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-31650 is a high-severity Incomplete Cleanup (CWE-459) vulnerability in Apache Tomcat. Its CVSS base score is 7.5 (High).

Operationally, ranked in the top 4.3% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

Deeper analysis

CVE-2025-31650 is an improper input validation vulnerability in Apache Tomcat that stems from incorrect error handling of certain invalid HTTP priority headers. The flaw leaves request objects incompletely cleaned up, producing a memory leak; repeated exploitation can exhaust heap memory and trigger an OutOfMemoryException. The issue affects Tomcat 9.0.76–9.0.102, 10.1.10–10.1.39, and 11.0.0-M2–11.0.5, as well as the end-of-life branches 8.5.90–8.5.100.

An unauthenticated remote attacker can send a stream of specially crafted HTTP requests containing malformed priority headers. Because no authentication or user interaction is required and the attack requires only network reachability, an adversary can induce a denial of service by forcing the server to terminate after memory exhaustion. The CVSS 3.1 score of 7.5 reflects the high availability impact combined with low attack complexity.

Apache Tomcat project advisories and downstream distributions such as Debian LTS recommend immediate upgrade to the fixed releases 9.0.104, 10.1.40, or 11.0.6. The referenced vendor announcements and oss-security postings contain the same upgrade guidance and note that no configuration work-arounds are provided.

EU & UK References

Vulnerability details

Improper Input Validation vulnerability in Apache Tomcat. Incorrect error handling for some invalid HTTP priority headers resulted in incomplete clean-up of the failed request which created a memory leak. A large number of such requests could trigger an OutOfMemoryException resulting…

more

in a denial of service. This issue affects Apache Tomcat: from 9.0.76 through 9.0.102, from 10.1.10 through 10.1.39, from 11.0.0-M2 through 11.0.5. The following versions were EOL at the time the CVE was created but are known to be affected: 8.5.90 though 8.5.100. Users are recommended to upgrade to version 9.0.104, 10.1.40 or 11.0.6 which fix the issue.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

apache
tomcat
11.0.0 · 9.0.76 — 9.0.104 · 10.1.10 — 10.1.40 · 11.0.1 — 11.0.6

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-459

Mandates complete sanitization during cleanup so that shared resources (memory, caches, buffers) do not retain data across subjects.

addresses: CWE-459

Operational retention schedules mandate complete cleanup of temporary or residual sensitive data after use.

addresses: CWE-459

Termination of the non-persistent artifact guarantees cleanup of temporary state, directly countering incomplete cleanup weaknesses.

addresses: CWE-459

Fail-safe procedures can explicitly require cleanup of temporary state, resources, or privileges on failure to avoid leaving the system in an inconsistent state.

addresses: CWE-459

The explicit delete step when information is no longer needed implements the cleanup that this weakness omits.

addresses: CWE-459

Enforces complete cleanup and sanitization steps during disposal, closing gaps that leave data remnants on retired components.

References