How severe is CVE-2021-36093?

CVE-2021-36093 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2021-36093 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-36093?

CVE-2021-36093 primarily affects Otrs. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-36093?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-36093 published?

CVE-2021-36093 was published on 2021-09-06 and last updated on 2026-06-17.

CVE-2021-36093

CVE-2021-36093 is a medium-severity vulnerability in Otrs with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-185.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 1% (62nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-185
Affected product: Otrs
Published: 2021-09-06
Last modified: 2026-06-17

Description

It's possible to create an email which can be stuck while being processed by PostMaster filters, causing DoS. 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 7.0.28 and prior versions; 8.0.x version 8.0.15 and prior versions.

Frequently asked questions

What is CVE-2021-36093?: It's possible to create an email which can be stuck while being processed by PostMaster filters, causing DoS. 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 7.0.28 and prior versions; 8.0.x version 8.0.15 and prior versions.
How severe is CVE-2021-36093?: CVE-2021-36093 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2021-36093 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (62nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-36093?: CVE-2021-36093 primarily affects Otrs. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-36093?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-36093 published?: CVE-2021-36093 was published on 2021-09-06 and last updated on 2026-06-17.

References

https://otrs.com/release-notes/otrs-security-advisory-2021-16/

Affected products (2)

cpe:2.3:a:otrs:otrs:*:*:*:*:community:*:*:*
cpe:2.3:a:otrs:otrs:*:*:*:*:-:*:*:*

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