CVE-2026-15565: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') in Red Hat Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 7
CVE-2026-15565 is a denial of service vulnerability in Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 7. It arises from a flaw in the Undertow component where a remote attacker can cause an out-of-memory condition on a WebSocket endpoint without authentication, specifically targeting any @ServerEndpoint class with an @OnMessage method. This vulnerability allows unauthenticated attackers to disrupt service availability using only a standard WebSocket handshake. A security update addressing this issue is available in Red Hat JBoss Enterprise Application Platform 7.4.25.
AI Analysis
Technical Summary
The vulnerability CVE-2026-15565 exists in the Undertow component of Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 7. It allows a remote attacker to cause an out-of-memory condition on WebSocket endpoints that implement any @ServerEndpoint class with an @OnMessage method. This can be exploited without authentication by performing a standard WebSocket handshake, resulting in a denial of service attack. The issue is fixed in Red Hat JBoss Enterprise Application Platform 7.4.25 as part of a security update.
Potential Impact
An unauthenticated remote attacker can cause a denial of service by exhausting memory resources on the affected system through the WebSocket endpoint. This results in service disruption without compromising confidentiality or integrity.
Mitigation Recommendations
A security update is available in Red Hat JBoss Enterprise Application Platform 7.4.25 that addresses this vulnerability. Users should apply this official fix to remediate the issue. No additional mitigation steps are required beyond applying the update.
CVE-2026-15565: Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') in Red Hat Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 7
Description
CVE-2026-15565 is a denial of service vulnerability in Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 7. It arises from a flaw in the Undertow component where a remote attacker can cause an out-of-memory condition on a WebSocket endpoint without authentication, specifically targeting any @ServerEndpoint class with an @OnMessage method. This vulnerability allows unauthenticated attackers to disrupt service availability using only a standard WebSocket handshake. A security update addressing this issue is available in Red Hat JBoss Enterprise Application Platform 7.4.25.
CVSS v3.1
Score 7.5high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-15565 exists in the Undertow component of Red Hat JBoss Enterprise Application Platform 7.4 ELS on RHEL 7. It allows a remote attacker to cause an out-of-memory condition on WebSocket endpoints that implement any @ServerEndpoint class with an @OnMessage method. This can be exploited without authentication by performing a standard WebSocket handshake, resulting in a denial of service attack. The issue is fixed in Red Hat JBoss Enterprise Application Platform 7.4.25 as part of a security update.
Potential Impact
An unauthenticated remote attacker can cause a denial of service by exhausting memory resources on the affected system through the WebSocket endpoint. This results in service disruption without compromising confidentiality or integrity.
Mitigation Recommendations
A security update is available in Red Hat JBoss Enterprise Application Platform 7.4.25 that addresses this vulnerability. Users should apply this official fix to remediate the issue. No additional mitigation steps are required beyond applying the update.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-356w-cx4r-75hv
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-15565"]
- Database Specific Severity
- HIGH
- Cvss Version
- 3.1
- State
- PUBLISHED
Patch Information
Threat ID: 6a7cd3f2bf8831d539180a53
Added to database: 08/12/2026, 20:13:38 UTC
Last enriched: 09/18/2026, 01:58:17 UTC
Last updated: 09/27/2026, 13:47:42 UTC
Views: 53
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