CVE-2025-53114

CometD has acknowledgement extension out of memory

State: Published
Severity: 7.5 High
Published: Jun 18, 2026
Updated: Jun 18, 2026
Reserved: Jun 25, 2025

Description

CometD is a scalable comet implementation for web messaging. In versions 5.0.0 through 5.0.22, 6.0.0 through 6.0.18, 7.0.0 through 7.0.18, and 8.0.0 through 8.0.8, bad clients that always send a fixed batch value when the server is using the acknowledgement extension may cause the unacknowledged message queue to grow indefinitely, eventually causing an `OutOfMemoryError`. Versions 5.0.23, 6.0.19, 7.0.19, and 8.0.9 patch the issue. As a workaround, disable the acknowledgement extension.

Scores

CVSS	Score	Vector	Source
3.1	7.5 High	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H	GitHub_M

Weaknesses

CWE-400 Uncontrolled Resource Consumption

Affected Products

Product	Versions
cometdcometd	>= 5.0.0, < 5.0.23Affected >= 6.0.0, < 6.0.19Affected >= 7.0.0, < 7.0.19Affected >= 8.0.0, < 8.0.9Affected

References

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