CVE-2021-39121

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.

Published: 2021-09-07 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-39121 is rated Low Risk (39.5/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.10%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-39121

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.24% 1.10% +0.87%
2 2025-12-22 0.40% 0.24% -0.17%
3 2025-11-21 — 0.40% —

Full EPSS history (12 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-39121

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 2.8 1.4 [email protected]
4.0 2.0 MEDIUM
AV:N/AC:L/Au:S/C:P/I:N/A:N Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
 8.0 2.9 [email protected]

Weakness enumeration for CVE-2021-39121

Affected software / configurations for CVE-2021-39121

Vendor Product Version Raw CPE
atlassian data_center < 8.5.18 cpe:2.3:a:atlassian:data_center:*:*:*:*:*:*:*:*
atlassian jira < 8.5.18 cpe:2.3:a:atlassian:jira:*:*:*:*:*:*:*:*
atlassian jira_data_center >= 8.6.0, < 8.13.10 cpe:2.3:a:atlassian:jira_data_center:*:*:*:*:*:*:*:*
atlassian jira_data_center >= 8.14.0, < 8.18.2 cpe:2.3:a:atlassian:jira_data_center:*:*:*:*:*:*:*:*
atlassian jira_server >= 8.6.0, < 8.13.10 cpe:2.3:a:atlassian:jira_server:*:*:*:*:*:*:*:*
atlassian jira_server >= 8.14.0, < 8.18.2 cpe:2.3:a:atlassian:jira_server:*:*:*:*:*:*:*:*

References for CVE-2021-39121

URL Tags
https://jira.atlassian.com/browse/JRASERVER-72715 Patch Vendor Advisory
cvelogic Threat Intelligence