CVE-2021-22886

Description

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.

Category

6.1
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.60%
Vendor Advisory rocket.chat
Affected: n/a Rocket.Chat
Published at:
Updated at:

References

Link Tags
https://docs.rocket.chat/guides/security/security-updates vendor advisory
https://hackerone.com/reports/1014459 third party advisory
https://github.com/RocketChat/Rocket.Chat/pull/20430 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-22886?
CVE-2021-22886 has been scored as a medium severity vulnerability.
How to fix CVE-2021-22886?
To fix CVE-2021-22886, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-22886 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-22886 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-22886?
CVE-2021-22886 affects n/a Rocket.Chat .
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