TI-2021-04537 Aliases CVE-2021-21439 GHSA-58p7-gj75-3437

Possible DoS attack using a special crafted URL in email body

LOW 30CWE-754Published 2021-06-14 · Updated 2024-09-16

Key facts

Attack vector: Network
Privileges required: None
User interaction: Required
Attack complexity: Low
Impact type: —
Confidentiality · integrity · availability: None · None · High
Fix status: No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

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.

Why it matters now

EPSS 0.00877 59th percentileScored 2026-11-07

Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
OTRS AG	((OTRS)) Community Edition	6.0.1 and later	—	No fix listed	CNA
OTRS AG	OTRS	7.0.x – 7.0.26; 8.0.x – 8.0.13	—	No fix listed	CNA

((OTRS)) Community Edition VendorOTRS AG Affected 6.0.1 and later Fixed in — No fix listed CNA
OTRS VendorOTRS AG Affected 7.0.x – 7.0.26; 8.0.x – 8.0.13 Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPE	Versions	Role	Vendor
cpe:2.3:a:otrs:otrs:::::community:::*	6.0.1 – 6.0.30	Vulnerable	OTRS AG
cpe:2.3:a:otrs:otrs::::::::	7.0.0 to before 7.0.27; 8.0.0 to before 8.0.14	Vulnerable	OTRS AG

cpe:2.3:a:otrs:otrs:*:*:*:*:community:*:*:* Versions 6.0.1 – 6.0.30 Vulnerable ·OTRS AG
cpe:2.3:a:otrs:otrs:*:*:*:*:*:*:*:* Versions 7.0.0 to before 7.0.27; 8.0.0 to before 8.0.14 Vulnerable ·OTRS AG

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2021-21439
2026-10-03 Alias added: GHSA-58p7-gj75-3437

References

Advisory 1

https://otrs.com/release-notes/otrs-security-advisory-2021-09/

Other 1

[debian-lts-announce] 20230831 [SECURITY] [DLA 3551-1] otrs2 security update

TI-2017-12458 In OTRS 6.0.x up to and including 6.0.1, OTRS 5.0.x up to and including 5.0.24, and OTRS… CVSS 3.0HIGH 8.8
TI-2026-35608 SQL Injection via MySQL Quote Method CVSS 3.1CRITICAL 9.1
TI-2023-04991 SSL Certificates are not checked for E-Mail Handling CVSS 3.1CRITICAL 9.1
TI-2022-04045 SQL Injection via OTRS Search API CVSS 3.1CRITICAL 9.8
TI-2017-12258 Code injection exists in Kernel/System/Spelling.pm in Open Ticket Request System (OTRS) 5… CVSS 3.0HIGH 8.8
TI-2017-06753 In Open Ticket Request System (OTRS) 3.3.x through 3.3.16, 4.x through 4.0.23, and 5.x… CVSS 3.0HIGH 8.8

See all 141 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences