CVE-2021-21439 - CVE House
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Status published Medium CVE-2021-21439

Possible DoS attack using a special crafted URL in email body

Vulnerability 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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

((OTRS)) Community Edition, OTRS
Vulnerable Versions:
6.0.1, 7.0.x, 8.0.x

Timeline

Official Publish: June 14th, 2021
Last Modified: September 16th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Weaknesses (CWE)

CWE-754

MITRE ATT&CK TTPs

T1190 Exploit Public-Facing Application
Initial Access
T1068 Exploitation for Privilege Escalation
Privilege Escalation
T1499 Endpoint Denial of Service
Impact
T1562 Impair Defenses
Defense Evasion
T1005 Data from Local System
Collection