CVE-2021-39127Network attack vector

Unauthenticated access to JQL endpoint

Published Oct 21, 2021 · Updated Oct 10, 2024

Broken access control in Atlassian Jira Server and Data Center before 8.5.10 and 8.6.0 through 8.13.0 allows attackers to access a JQL endpoint. The query component accepts endpoint requests without enforcing authentication, exposing JQL functionality outside its intended access boundary. No account or user interaction is required; Atlassian has not disclosed the precise JQL operations or data made accessible.

CVSS severity5.3
Medium
EPSS probability1.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Broken access control in Atlassian Jira Server and Data Center before 8.5.10 and 8.6.0 through 8.13.0 allows attackers to access a JQL endpoint. The query component accepts endpoint requests without enforcing authentication, exposing JQL functionality outside its intended access boundary. No account or user interaction is required; Atlassian has not disclosed the precise JQL operations or data made accessible.

The record

CVE
CVE-2021-39127
Published
Oct 21, 2021
Updated
Oct 10, 2024
Vendor
Atlassian
Product
Jira Server
Classifications
T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 21, 2021CVE publishedPublication date reported by the CVE source.
  2. Oct 10, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <8.5.10
  2. Affected versionversion=8.6.0 <8.13.1
  3. Affected versionversion=8.6.0 <unspecified
  4. Affected versionversion=unspecified <8.13.1
  5. Affected versionversion=unspecified <8.5.10

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Atlassian · Jira Serverversion=0 <8.5.10; version=8.6.0 <8.13.1; version=8.6.0 <unspecified; version=unspecified <8.13.1; version=unspecified <8.5.10
Atlassian · Jira Data Centerversion=0 <8.5.10; version=8.6.0 <8.13.1; version=8.6.0 <unspecified; version=unspecified <8.13.1; version=unspecified <8.5.10

Published CVSS scores

5.0NISTAV:N/AC:L/Au:N/C:N/I:P/A:N
5.3NISTCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
5.3CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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