How severe is CVE-2025-53114?

CVE-2025-53114 has a CVSS score of 7.5/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2025-53114?

CVE-2025-53114 affects the following packages: org.cometd.java:cometd-java-server-common (Maven), org.cometd.java:cometd-java-server-common (Maven), org.cometd.java:cometd-java-server-common (Maven), org.cometd.java:cometd-java-server-common (Maven). Ecosystems affected: Maven.

How do I fix CVE-2025-53114?

Update org.cometd.java:cometd-java-server-common to 5.0.23 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-53114 is resolved across your whole dependency graph.

How do I detect CVE-2025-53114 in my Maven dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.cometd.java:cometd-java-server-common, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2025-53114 if there is no patch (or I can't update yet)?

Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Is CVE-2025-53114 actively exploited in the wild?

No public exploit code has been indexed for CVE-2025-53114 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2025-53114?

CVE-2025-53114 has an EPSS (Exploit Prediction Scoring System) score of 0.7%, placing it in the 51th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2025-53114?

CVE-2025-53114 is classified as Uncontrolled Resource Consumption (CWE-400). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2025-53114 published, and has it been updated?

CVE-2025-53114 was published on June 18, 2026 and was last updated on August 12, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

☕

☕ Maven

Not in CISA KEV

HIGH severity

CVE-2025-53114 — cometd-java-server-common

HIGHFix: cometd/cometd#2118

CVE-2025-53114 is a high-severity (CVSS 7.5) Uncontrolled Resource Consumption vulnerability in org.cometd.java:cometd-java-server-common. A fix is available for org.cometd.java:cometd-java-server-common — see the affected versions and patch details below.

CometD has acknowledgement extension out of memory

Also known asGHSA-cqgj-h8vf-4w59

Published

Jun 18, 2026

Updated

Aug 12, 2026

Affected

4 pkgs

Patched

4 / 4

Exploits

None indexed

Exploitation data as of Sep 27, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2025-53114.

EPSS Exploitation Probability

via FIRST.org ↗

0.7%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs51th percentile — riskier than 51% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2025-53114 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 380,066 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

Real-World Exposure

4 pkgs affected

☕org.cometd.java:cometd-java-server-common☕org.cometd.java:cometd-java-server-common☕org.cometd.java:cometd-java-server-common☕org.cometd.java:cometd-java-server-common

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.

Description

Impact

Bad clients that always send a fixed batch value while the server is using the acknowledgement extension can cause the unacknowledged message queue to grow indefinitely, eventually resulting in an OutOfMemoryError.

Such bad clients would always send:

{
  "channel": "/meta/connect",
  ...
  "ext": { "ack": 1 }
}

The server would never clear the unacknowledged message queue, and one bad client can cause a server outage.

Patches

5.0.x - https://github.com/cometd/cometd/pull/2168 6.0.x - https://github.com/cometd/cometd/pull/2169 8.0.x - https://github.com/cometd/cometd/pull/2118

Workarounds

Disable the acknowledgement extension.

Resources

https://github.com/cometd/cometd/discussions/2116 https://github.com/cometd/cometd/issues/2117

Affected Packages

4 total 4 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`org.cometd.java:cometd-java-server-common`	≥ 5.0.0&&< 5.0.23	5.0.23`org.cometd.java:cometd-java-server-common:5.0.23`
☕Maven	`org.cometd.java:cometd-java-server-common`	≥ 6.0.0&&< 6.0.19	6.0.19`org.cometd.java:cometd-java-server-common:6.0.19`
☕Maven	`org.cometd.java:cometd-java-server-common`	≥ 7.0.0&&< 7.0.19	7.0.19`org.cometd.java:cometd-java-server-common:7.0.19`
☕Maven	`org.cometd.java:cometd-java-server-common`	≥ 8.0.0&&< 8.0.9	8.0.9`org.cometd.java:cometd-java-server-common:8.0.9`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.cometd.java:cometd-java-server-common, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.cometd.java:cometd-java-server-common to 5.0.23 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-53114 is resolved across your whole dependency graph.
Workarounds
Cap what an attacker can consume: apply request size, rate and timeout limits in front of the affected component, and run it with memory and CPU limits so exhaustion degrades one worker rather than the whole service.

Frequently Asked Questions

### Impact Bad clients that always send a fixed batch value while the server is using the acknowledgement extension can cause the unacknowledged message queue to grow indefinitely, eventually resulting in an OutOfMemoryError. Such bad clients would always send: ```json { "channel": "/meta/connect", ... "ext": { "ack": 1 } } ``` The server would never clear the unacknowledged message queue, and one bad client can cause a server outage. ### Patches 5.0.x - https://github.com/cometd/cometd/pull/2168 6.0.x - https://github.com/cometd/cometd/pull/2169 8.0.x - https://github.com/cometd/com