CWE
79
Advisory Published
Updated

CVE-2021-22886: XSS

First published: Fri Mar 26 2021(Updated: )

Rocket.Chat before 3.11, 3.10.5, 3.9.7, 3.8.8 is vulnerable to persistent cross-site scripting (XSS) using nested markdown tags allowing a remote attacker to inject arbitrary JavaScript in a message. This flaw leads to arbitrary file read and RCE on Rocket.Chat desktop app.

Credit: support@hackerone.com

Affected SoftwareAffected VersionHow to fix
Rocket.Chat Livechat<3.8.8
Rocket.Chat Livechat>=3.9.0<3.9.7
Rocket.Chat Livechat>=3.10.0<3.10.5
Rocket.Chat Livechat=3.11.0-rc0
Rocket.Chat Livechat=3.11.0-rc1
Rocket.Chat Livechat=3.11.0-rc2
Rocket.Chat Livechat=3.11.0-rc3
Rocket.Chat Livechat=3.11.0-rc4
Rocket.Chat Livechat=3.11.0-rc5
Rocket.Chat Livechat=3.11.0-rc6
Rocket.Chat Livechat=3.11.0-rc7

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Frequently Asked Questions

  • What is the severity of CVE-2021-22886?

    CVE-2021-22886 is a high-severity vulnerability that allows for persistent cross-site scripting (XSS) in Rocket.Chat.

  • How do I fix CVE-2021-22886?

    To fix CVE-2021-22886, upgrade Rocket.Chat to version 3.11.0 or later.

  • What types of attacks can CVE-2021-22886 facilitate?

    CVE-2021-22886 can facilitate arbitrary file read and remote code execution (RCE) through malicious messages.

  • Which versions of Rocket.Chat are affected by CVE-2021-22886?

    CVE-2021-22886 affects Rocket.Chat versions before 3.11, 3.10.5, 3.9.7, and 3.8.8.

  • Is CVE-2021-22886 related to user input?

    Yes, CVE-2021-22886 is related to user input via nested markdown tags that can lead to XSS vulnerabilities.

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