CVE-2021-21439

Possible DoS attack using a special crafted URL in email body

Description

DoS attack can be performed when an email contains specially designed URL in the body. It can lead to the high CPU usage and cause low quality of service, or in extreme case bring the system to a halt. This issue affects: OTRS AG ((OTRS)) Community Edition 6.0.x version 6.0.1 and later versions. OTRS AG OTRS 7.0.x version 7.0.26 and prior versions; 8.0.x version 8.0.13 and prior versions.

Remediation

Solution:

  • Update to OTRS 8.0.14 or OTRS 7.0.27.

Categories

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.33%
Vendor Advisory otrs.com
Affected: OTRS AG ((OTRS)) Community Edition
Affected: OTRS AG OTRS
Published at:
Updated at:

References

Link Tags
https://otrs.com/release-notes/otrs-security-advisory-2021-09/ vendor advisory
https://lists.debian.org/debian-lts-announce/2023/08/msg00040.html mailing list

Frequently Asked Questions

What is the severity of CVE-2021-21439?
CVE-2021-21439 has been scored as a medium severity vulnerability.
How to fix CVE-2021-21439?
To fix CVE-2021-21439: Update to OTRS 8.0.14 or OTRS 7.0.27.
Is CVE-2021-21439 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-21439 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-2021-21439?
CVE-2021-21439 affects OTRS AG ((OTRS)) Community Edition, OTRS AG OTRS.
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