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Advisory details: gitlab / maven/org.apache.activemq/apache-activemq/CVE-2025-66168
Advisory ID gitlab/maven/org.apache.activemq/apache-activemq/CVE-2025-66168
Aliases CVE-2025-66168
GHSA-c825-6ph3-4h84
Summary Apache ActiveMQ is Vulnerable to Integer Overflow or Wraparound 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.
Status Published
Exploitability 0.5
Weighted Severity 0.0
Risk
Affected and Fixed Packages Package Details
Introduced and Fixed Package Commit Patches Package Commit Patches Details
Weaknesses (3)
CWE-190 Integer Overflow or Wraparound
CWE-937 OWASP Top Ten 2013 Category A9 - Using Components with Known Vulnerabilities
CWE-1035 OWASP Top Ten 2017 Category A9 - Using Components with Known Vulnerabilities
System Score Found at
cvssv3.1 https://gitlab.com/gitlab-org/advisories-community/-/blob/main/maven/org.apache.activemq/apache-activemq/CVE-2025-66168.yml
Reference id Reference type URL
https://github.com/apache/activemq
13n8mkrb2jf2y6yyhpgrkmpqcm7djyto Advisory https://lists.apache.org/thread/13n8mkrb2jf2y6yyhpgrkmpqcm7djyto
CVE-2025-66168 https://nvd.nist.gov/vuln/detail/CVE-2025-66168
CVE-2026-40046-announcement.txt Other https://activemq.apache.org/security-advisories.data/CVE-2026-40046-announcement.txt
CVERecord?id=CVE-2026-40046 Other https://www.cve.org/CVERecord?id=CVE-2026-40046
GHSA-c825-6ph3-4h84 https://github.com/advisories/GHSA-c825-6ph3-4h84
No exploits are available.

No EPSS data available for this advisory.

Patch URL
There are no known patches.
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N Found at https://gitlab.com/gitlab-org/advisories-community/-/blob/main/maven/org.apache.activemq/apache-activemq/CVE-2025-66168.yml
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none

Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2026-03-04T20:27:42Z/

Decision: Track

Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2025/66xxx/CVE-2025-66168.json

Source Advisory: vulnrichment/CVE-2025-66168

View SSVC decision tree 
[{'Exploitation': 'none'},
 {'Automatable': 'no'},
 {'Technical Impact': 'partial'},
 {'Mission Prevalence': 'minimal'},
 {'Public Well-being Impact': 'material'},
 {'Mission & Well-being': 'medium'}]