CVE-2021-21439

mediumpriority · track · 26EPSS 0.009 · 59 %ileDEEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.88% (59th) EPSS

CVSS 4.3 · medium

Is it mine?

13 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

6.5

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 8.6 · impact 2.9

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 3.6

v3.16.5mediumAV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Hsecondary · ENISA EU

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Hsecondary · security@otrs.comexploitability 2.8 · impact 3.6

v3.16mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-755USprimaryCWE-754USCWE-755US

affected products (13)

Products and version ranges known to be affected.

Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
OTRS AG ((OTRS)) Community Edition6.0.1 → 6.0.x*enisa_euvdEU
OTRS AG OTRS≤ 8.0.x ≤8.0.13enisa_euvdEU
OTRS AG OTRS≤ 7.0.x ≤7.0.26enisa_euvdEU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 9fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 10fstec_bduRU
Сообщество свободного программного обеспечения Debian GNU/Linux≤ 8fstec_bduRU
Сообщество свободного программного обеспечения OTRS6.0.1 → 6.0.30fstec_bduRU
Сообщество свободного программного обеспечения OTRS7.0.0 → 7.0.27fstec_bduRU
Сообщество свободного программного обеспечения OTRS8.0.0 → 8.0.14fstec_bduRU
otrs otrs6.0.1 → 6.0.30nvdUScpe:2.3:a:otrs:otrs:*:*:*:*:*:*:*:*
otrs otrs7.0.0 → 7.0.27nvdUScpe:2.3:a:otrs:otrs:*:*:*:*:*:*:*:*
otrs otrs8.0.0 → 8.0.14nvdUScpe:2.3:a:otrs:otrs:*:*:*:*:*:*:*:*

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2023-2219OTRS: Mehrere SchwachstellenDeutsch2021-06-16csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in OTRS ausnutzen, um einen Denial of Service oder Cross Site Scripting Angriff durchzuführen.

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund nvd NVD CVE.org MITRE

published 2021-06-14modified 2026-06-17

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+700 more

references (8)

External citations — patches, advisories, analysis.

scry

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