CVE-2026-53916
Description
From CVE.org
Memory Allocation with Excessive Size Value vulnerability in Apache ActiveMQ, Apache ActiveMQ All, Apache ActiveMQ Stomp. An unauthenticated client that opens a STOMP NIO connection can send header bytes that never terminate which makes the broker buffer them without limit, exhausting the JVM heap. This issue affects Apache ActiveMQ: before 5.19.8, from 6.0.0 before 6.2.7; Apache ActiveMQ All: before 5.19.8, from 6.0.0 before 6.2.7; Apache ActiveMQ Stomp: before 5.19.8, from 6.0.0 before 6.2.7. Users are recommended to upgrade to version 6.2.7 or 5.19.8, which fixes the issue.
Statement
Red Hat products ship Apache ActiveMQ Classic components as transitive dependencies. The vulnerability is in the Classic ActiveMQ STOMP NIO codec, which does not limit the size of header byte buffering, allowing an unauthenticated attacker to exhaust JVM heap memory. Apache ActiveMQ Artemis, which powers Red Hat AMQ Broker, has its own STOMP protocol implementation (artemis-stomp-protocol) that does not share this code path. The Classic STOMP NIO codec is not exposed in Red Hat product deployments.
Mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.5 | N/A | 7.5 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | None |
| Integrity Impact | None | N/A | None |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (Memory)
Not controlling memory allocation can result in a request for too much system memory, possibly leading to a crash of the application due to out-of-memory conditions, or the consumption of a large amount of memory on the system.
Frequently Asked Questions
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