How severe is CVE-2021-37553?

CVE-2021-37553 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2021-37553 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-37553?

CVE-2021-37553 affects Jetbrains Youtrack. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-37553?

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

When was CVE-2021-37553 published?

CVE-2021-37553 was published on 2021-08-06 and last updated on 2026-06-17.

CVE-2021-37553

CVE-2021-37553 is a high-severity vulnerability in Jetbrains Youtrack with a CVSS 3.x base score of 7.5. 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-338.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 1% (70th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-338
Affected product: Jetbrains Youtrack
Published: 2021-08-06
Last modified: 2026-06-17

Description

In JetBrains YouTrack before 2021.2.16363, an insecure PRNG was used.

Frequently asked questions

What is CVE-2021-37553?: In JetBrains YouTrack before 2021.2.16363, an insecure PRNG was used.
How severe is CVE-2021-37553?: CVE-2021-37553 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2021-37553 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-37553?: CVE-2021-37553 affects Jetbrains Youtrack. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-37553?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-37553 published?: CVE-2021-37553 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:youtrack:*:*:*:*:*:*:*:*

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Other CWE-338 vulnerabilities

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CVE-2026-2439 — Critical (CVSS 9.8): Concierge::Sessions versions from 0.8.1 before 0.8.5 for Perl generate insecure session ids. The generate_session_id…
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