What’s Vulnerable › Vulnerabilities

CVE-2021-39121

• Severity: medium (CVSS 4.3 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.6% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-09-08 · updated 2026-06-17

Description

Affected versions of Atlassian Jira Server and Data Center allow authenticated remote attackers to enumerate the keys of private Jira projects via an Information Disclosure vulnerability in the /rest/api/latest/projectvalidate/key endpoint. The affected versions are before version 8.5.18, from version 8.6.0 before 8.13.10, and from version 8.14.0 before 8.18.2.

Affected products

• Atlassian Data Center: before 8.5.18 — fixed in 8.5.18
• Atlassian Jira: before 8.5.18 — fixed in 8.5.18
• Atlassian Jira: from 8.6.0 before 8.13.10; from 8.14.0 before 8.18.2 — fixed in 8.13.10, 8.18.2
• Atlassian Jira: from 8.6.0 before 8.13.10; from 8.14.0 before 8.18.2 — fixed in 8.13.10, 8.18.2

How to fix

Upgrade to a fixed version: Atlassian Data Center 8.5.18; Atlassian Jira 8.5.18; Atlassian Jira 8.13.10, 8.18.2; Atlassian Jira 8.13.10, 8.18.2. Check the vendor advisory for mitigations.

References

• https://jira.atlassian.com/browse/JRASERVER-72715
• https://jira.atlassian.com/browse/JRASERVER-72715

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