CVE-2025-66168
MEDIUM
GHSA-c825-6ph3-4h84
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
Lifecycle Timeline
3Description
Apache ActiveMQ does not properly validate the remaining length field which may lead to an overflow during the decoding of malformed packets. When this integer overflow occurs, ActiveMQ may incorrectly compute the total Remaining Length and subsequently misinterpret the payload as multiple MQTT control packets which makes the broker susceptible to unexpected behavior when interacting with non-compliant clients. This behavior violates the MQTT v3.1.1 specification, which restricts Remaining Length to a maximum of 4 bytes. The scenario occurs on established connections after the authentication process. Brokers that are not enabling mqtt transport connectors are not impacted. This issue affects Apache ActiveMQ: before 5.19.2, 6.0.0 to 6.1.8, and 6.2.0 Users are recommended to upgrade to version 5.19.2, 6.1.9, or 6.2.1, which fixes the issue.
Analysis
Apache ActiveMQ does not properly validate the remaining length field which may lead to an overflow during the decoding of malformed packets. [CVSS 5.4 MEDIUM]
Technical Context
Classified as CWE-190 (Integer Overflow or Wraparound). Affects Activemq. Apache ActiveMQ does not properly validate the remaining length field which may lead to an overflow during the decoding of malformed packets. When this integer overflow occurs, ActiveMQ may incorrectly compute the total Remaining Length and subsequently misinterpret the payload as multiple MQTT control packets which makes the broker susceptible to unexpected behavior when interacting with non-compliant clients. This behavior violates the MQTT v3.1.1 specification, which restricts Remaining Lengt
Affected Products
Vendor: Apache. Product: Activemq.
Remediation
Update to version 5.19.2 or later. Restrict network access to the affected service where possible.
Priority Score
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External POC / Exploit Code
Leaving vuln.today