How severe is CVE-2021-27733?

CVE-2021-27733 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-27733 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-27733?

CVE-2021-27733 affects Jetbrains Youtrack. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-27733?

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

When was CVE-2021-27733 published?

CVE-2021-27733 was published on 2021-05-11 and last updated on 2026-06-17.

CVE-2021-27733

CVE-2021-27733 is a medium-severity vulnerability in Jetbrains Youtrack with a CVSS 3.x base score of 5.4. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
CVSS v2: 3.5
EPSS exploit prediction: 1% (46th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Jetbrains Youtrack
Published: 2021-05-11
Last modified: 2026-06-17

Description

In JetBrains YouTrack before 2020.6.6441, stored XSS was possible via an issue attachment.

Frequently asked questions

What is CVE-2021-27733?: In JetBrains YouTrack before 2020.6.6441, stored XSS was possible via an issue attachment.
How severe is CVE-2021-27733?: CVE-2021-27733 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-27733 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-27733?: CVE-2021-27733 affects Jetbrains Youtrack. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-27733?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-27733 published?: CVE-2021-27733 was published on 2021-05-11 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:jetbrains:youtrack:*:*:*:*:*:*:*:*

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