CVE-2023-37544Network attack vector

Service interruption via unauthenticated ping/pong servlet

Published Dec 20, 2023 · Updated Feb 13, 2025

Improper authentication in Apache Pulsar WebSocket Proxy allows remote attackers to access /pingpong without credentials. WebSocketServiceStarter and related broker and proxy startup paths register WebSocketPingPongServlet without enforcing authentication for that endpoint. Any network client that can reach the WebSocket listener can open these connections and misuse ping/pong traffic to interrupt service or drive excessive data transfer.

CVSS severity7.5
High
EPSS probability1.35%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authentication in Apache Pulsar WebSocket Proxy allows remote attackers to access /pingpong without credentials. WebSocketServiceStarter and related broker and proxy startup paths register WebSocketPingPongServlet without enforcing authentication for that endpoint. Any network client that can reach the WebSocket listener can open these connections and misuse ping/pong traffic to interrupt service or drive excessive data transfer.

The record

CVE
CVE-2023-37544
Published
Dec 20, 2023
Updated
Feb 13, 2025
Vendor
The Apache Software Foundation
Product
Apache Pulsar WebSocket Proxy
Classifications
CWE-287, T1499.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 20, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 13, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=2.10.0 <=2.10.4
  2. Affected versionversion=2.11.0 <=2.11.1
  3. Affected versionversion=2.8.0 <=2.8.*
  4. Affected versionversion=2.9.0 <=2.9.*
  5. Affected versionversion=3.0.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Apache Software Foundation · Apache Pulsar WebSocket Proxyversion=2.10.0 <=2.10.4; version=2.11.0 <=2.11.1; version=2.8.0 <=2.8.*; version=2.9.0 <=2.9.*; version=3.0.0

Published CVSS scores

7.5Apache Software FoundationCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-287Improper Authentication
T1499.002Service Exhaustion Flood

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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