CVE-2026-108949
Description
A flaw was found in Apache ActiveMQ. When an authenticated client requests access to a temporary destination owned by another connection, the broker rejects the request but fails to remove the rejected subscription entry from internal memory. By repeatedly issuing these requests, an authenticated attacker can cause an unbounded memory leak, ultimately leading to an Out-of-Memory (OOM) condition and a Denial of Service (DoS) for the broker.
Statement
An authenticated remote user can leak broker heap via repeated rejected temporary-destination consumer requests until OOM; upgrade to activemq-broker 6.4.0/6.3.3 or 5.19.12; requiring broker-side OpenWire authentication mitigates anonymous exploitation.
Mitigation
Upgrade to fixed versions (activemq-broker 6.4.0, 6.3.3, or 5.19.12); restrict broker authentication and monitor broker heap.
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 | 6.5 | N/A | 6.5 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | Low | N/A | Low |
| 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:L/UI:N/S:U/C:N/I:N/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (Other); DoS: Resource Consumption (Memory); DoS: Resource Consumption (CPU)
An attacker that can influence the allocation of resources that are not properly released could deplete the available resource pool and prevent all other processes from accessing the same type of resource. Frequently-affected resources include memory, CPU, disk space, power or battery, etc.
Frequently Asked Questions
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