CVE-2021-37865

Server-side Denial of Service while processing a specifically crafted GIF file

Description

Mattermost 6.2 and earlier fails to sufficiently process a specifically crafted GIF file when it is uploaded while drafting a post, which allows authenticated users to cause resource exhaustion while processing the file, resulting in server-side Denial of Service.

Category

4.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.37%
Vendor Advisory mattermost.com
Affected: Mattermost Mattermost
Published at:
Updated at:

References

Link Tags
https://mattermost.com/security-updates/ vendor advisory
https://hackerone.com/reports/1428260 permissions required

Frequently Asked Questions

What is the severity of CVE-2021-37865?
CVE-2021-37865 has been scored as a medium severity vulnerability.
How to fix CVE-2021-37865?
To fix CVE-2021-37865, 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-2021-37865 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-37865 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-37865?
CVE-2021-37865 affects Mattermost Mattermost .
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