Vulnerability from bitnami_vulndb
Denial of Service via Out of Memory vulnerability in Apache ActiveMQ Client, Apache ActiveMQ Broker, Apache ActiveMQ.
ActiveMQ NIO SSL transports do not correctly handle TLSv1.3 handshake KeyUpdates triggered by clients. This makes it possible for a client to rapidly trigger updates which causes the broker to exhaust all its memory in the SSL engine leading to DoS.
Note: TLS versions before TLSv1.3 (such as TLSv1.2) are broken but are not vulnerable to OOM. Previous TLS versions require a full handshake renegotiation which causes a connection to hang but not OOM. This is fixed as well. This issue affects Apache ActiveMQ Client: before 5.19.4, from 6.0.0 before 6.2.4; Apache ActiveMQ Broker: before 5.19.4, from 6.0.0 before 6.2.4; Apache ActiveMQ: before 5.19.4, from 6.0.0 before 6.2.4.
Users are recommended to upgrade to version 6.2.4 or 5.19.5, which fixes the issue.
{
"affected": [
{
"package": {
"ecosystem": "Bitnami",
"name": "activemq",
"purl": "pkg:bitnami/activemq"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "5.19.4"
},
{
"introduced": "6.0.0"
},
{
"fixed": "6.2.4"
}
],
"type": "SEMVER"
}
],
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"type": "CVSS_V3"
}
]
}
],
"aliases": [
"CVE-2026-39304"
],
"database_specific": {
"cpes": [
"cpe:2.3:a:apache:activemq:*:*:*:*:*:maven:*:*"
],
"severity": "High"
},
"details": "Denial of Service via Out of Memory vulnerability in Apache ActiveMQ Client, Apache ActiveMQ Broker, Apache ActiveMQ.\n\nActiveMQ NIO SSL transports do not correctly handle TLSv1.3 handshake KeyUpdates triggered by clients. This makes it possible for a client to rapidly trigger updates which causes the broker to exhaust all its memory in the SSL engine leading to DoS.\n\nNote: TLS versions before TLSv1.3 (such as TLSv1.2) are broken but are not vulnerable to OOM. Previous TLS versions require a full handshake renegotiation which causes a connection to hang but not OOM. This is fixed as well.\nThis issue affects Apache ActiveMQ Client: before 5.19.4, from 6.0.0 before 6.2.4; Apache ActiveMQ Broker: before 5.19.4, from 6.0.0 before 6.2.4; Apache ActiveMQ: before 5.19.4, from 6.0.0 before 6.2.4.\n\nUsers are recommended to upgrade to version 6.2.4 or 5.19.5, which fixes the issue.",
"id": "BIT-activemq-2026-39304",
"modified": "2026-04-17T00:10:47.507Z",
"published": "2026-04-16T23:36:26.790Z",
"references": [
{
"type": "WEB",
"url": "http://www.openwall.com/lists/oss-security/2026/04/09/17"
},
{
"type": "WEB",
"url": "https://activemq.apache.org/security-advisories.data/CVE-2026-39304-announcement.txt"
},
{
"type": "WEB",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-39304"
}
],
"schema_version": "1.6.2",
"summary": "Apache ActiveMQ Client, Apache ActiveMQ Broker, Apache ActiveMQ All, Apache ActiveMQ: Incorrect handling of TLSv1.3 KeyUpdate can be exploited to cause DoS via OOM"
}
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.