How severe is CVE-2021-37544?

CVE-2021-37544 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-37544 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-37544?

CVE-2021-37544 affects Jetbrains Teamcity. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-37544?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2021-37544 published?

CVE-2021-37544 was published on 2021-08-06 and last updated on 2026-06-17.

CVE-2021-37544

CVE-2021-37544 is a critical-severity vulnerability in Jetbrains Teamcity with a CVSS 3.x base score of 9.8. 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-502.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 1% (65th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-502
Affected product: Jetbrains Teamcity
Published: 2021-08-06
Last modified: 2026-06-17

Description

In JetBrains TeamCity before 2020.2.4, there was an insecure deserialization.

Frequently asked questions

What is CVE-2021-37544?: In JetBrains TeamCity before 2020.2.4, there was an insecure deserialization.
How severe is CVE-2021-37544?: CVE-2021-37544 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-37544 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-37544?: CVE-2021-37544 affects Jetbrains Teamcity. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-37544?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2021-37544 published?: CVE-2021-37544 was published on 2021-08-06 and last updated on 2026-06-17.

References

https://blog.jetbrains.com/blog/2021/08/05/jetbrains-security-bulletin-q2-2021/

Affected products (1)

cpe:2.3:a:jetbrains:teamcity:*:*:*:*:*:*:*:*

More vulnerabilities in Jetbrains Teamcity

CVE-2024-27198 — Critical (CVSS 9.8): In JetBrains TeamCity before 2023.11.4 authentication bypass allowing to perform admin actions was possible
CVE-2024-23917 — Critical (CVSS 9.8): In JetBrains TeamCity before 2023.11.3 authentication bypass leading to RCE was possible
CVE-2023-42793 — Critical (CVSS 9.8): In JetBrains TeamCity before 2023.05.4 authentication bypass leading to RCE on TeamCity Server was possible
CVE-2022-25263 — Critical (CVSS 9.8): JetBrains TeamCity before 2021.2.3 was vulnerable to OS command injection in the Agent Push feature configuration.
CVE-2022-24340 — Critical (CVSS 9.8): In JetBrains TeamCity before 2021.2.1, XXE during the parsing of the configuration file was possible.
CVE-2022-24331 — Critical (CVSS 9.8): In JetBrains TeamCity before 2021.1.4, GitLab authentication impersonation was possible.

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