CVE-2026-50734

Apache ActiveMQ Client, Apache ActiveMQ, Apache ActiveMQ All: Pre-authentication OpenWire memory-allocation DoS during wire format negotiation

HIGH
7.5
CVSS Score
Published: June 30, 2026 at 09:53 AM UTC
Updated: July 2, 2026 at 06:58 PM UTC
2 products affected across 1 vendorActiveMQActiveMQ All

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Severity
HIGH7.5
Exploit prediction
EPSS 0.7%
SSVC
No known exploit

Description

Memory Allocation with Excessive Size Value vulnerability in Apache ActiveMQ Client, Apache ActiveMQ, Apache ActiveMQ All. An unauthenticated network attacker can cause a broker DoS by sending a crafted WireFormatInfo frame with a malicious large size value. The value is not validate and causes the broker to attempt allocation during pre-auth negotiation which can trigger OOM and crash the broker. This issue affects Apache ActiveMQ Client: before 5.19.8, from 6.0.0 before 6.2.7; 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. Users are recommended to upgrade to version 6.2.7 or 5.19.8, which fixes the issue.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 5.19.86.0.0 ≤ v < 6.2.76.0.0
Affected range stops below 5.19.8, so it looks safe — our inference, not a vendor statement
Affected range stops below 6.2.7, so it looks safe — our inference, not a vendor statement
v < 5.19.86.0.0 ≤ v < 6.2.76.0.0
Affected range stops below 5.19.8, so it looks safe — our inference, not a vendor statement
Affected range stops below 6.2.7, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (2)

Vendor AdvisoryMailing List
Source: cverecord
https://lists.apache.org/thread/nxso951fnvf72qf9m475mpz4yf931xk0
Third Party Advisory
Source: af854a3a-2127-422b-91ae-364da2661108
http://www.openwall.com/lists/oss-security/2026/06/29/10

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHCISA-ADP
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-789

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