CVE-2025-5892Public exploitNetwork attack vector

Authenticated server hang via IRC parser ReDoS

Published Jun 9, 2025 · Updated Jun 9, 2025

Inefficient regular expression complexity in Rocket.Chat 7.6.0 and 7.6.1 allows remote authenticated users to hang the server. The RFC2813 parseMessage function applies /^:|\s+:/ to an attacker-controlled IRC line; a long space sequence ending in a null byte forces excessive matching work and CPU use. Access to the IRC message-processing path is required, and successful exploitation affects availability without reported data disclosure or modification.

CVSS severity7.5
High
EPSS probability0.60%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Inefficient regular expression complexity in Rocket.Chat 7.6.0 and 7.6.1 allows remote authenticated users to hang the server. The RFC2813 parseMessage function applies /^:|\s+:/ to an attacker-controlled IRC line; a long space sequence ending in a null byte forces excessive matching work and CPU use. Access to the IRC message-processing path is required, and successful exploitation affects availability without reported data disclosure or modification.

The record

CVE
CVE-2025-5892
Published
Jun 9, 2025
Updated
Jun 9, 2025
Vendor
Rocket.Chat Technologies Corp.
Product
Rocket.Chat
Classifications
CWE-1333, CWE-400, T1499.004
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 9, 2025CVE publishedPublication date reported by the CVE source.
  2. Jun 9, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

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

  1. Affected versionversion=7.6.0
  2. Affected versionversion=7.6.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Rocket.Chat Technologies Corp. · Rocket.Chatversion=7.6.0; version=7.6.1

Published CVSS scores

4.0VulDB CNAAV:N/AC:L/Au:S/C:N/I:N/A:P/E:POC/RL:TF/RC:UR
4.3VulDB CNACVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:T/RC:R
2.1VulDB CNACVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P
4.3VulDB CNACVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L/E:P/RL:T/RC:R
7.5NIST NVDCVSS: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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-1333Inefficient Regular Expression Complexity
CWE-400Uncontrolled Resource Consumption
T1499.004Application or System Exploitation

Public exploit references

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

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo