CVE-2023-28356 Denial of service in Rocket.Chat

High 7.5 Published 11 May 2023 Updated 27 Jan 2025

A maliciously crafted message causes a hot loop in Rocket.Chat, consuming excessive CPU and rendering the service unresponsive.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2023-28356?

CVE-2023-28356 is a high-severity denial of service vulnerability in Rocket.chat Rocket.chat, published on 11 May 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A vulnerability has been identified where a maliciously crafted message containing a specific chain of characters can cause the chat to enter a hot loop on one of the processes, consuming ~120% CPU and rendering the service unresponsive.

Weakness: CWE-770, CWE-400

Which versions are affected by CVE-2023-28356?

It affects 1 product.

Products include Rocket.chat Rocket.chat.

How do I fix CVE-2023-28356?

No fix has been published for CVE-2023-28356 yet. Limit exposure of the affected software until one is available.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2023-28356 being exploited?

There is no known exploitation of CVE-2023-28356 in the wild and no public exploit code.

All Rocket.chat Rocket.chat vulnerabilities

Sources

Also known as GHSA-cw96-grj5-m243.