CVE-2021-39117Network attack vector

Stored XSS via unescaped custom-field names

Published Aug 30, 2021 · Updated Oct 11, 2024

Stored XSS in Atlassian Jira Server and Data Center 8.15.0 through 8.17.x allows remote attackers to inject HTML or JavaScript. AssociateFieldToScreens renders an administrator-supplied custom-field name without neutralizing markup, storing the payload for later execution. Creating the custom field requires high privileges, and script execution requires another user to view the affected page; impact is limited to that user's browser context.

CVSS severity4.8
Medium
EPSS probability0.64%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in Atlassian Jira Server and Data Center 8.15.0 through 8.17.x allows remote attackers to inject HTML or JavaScript. AssociateFieldToScreens renders an administrator-supplied custom-field name without neutralizing markup, storing the payload for later execution. Creating the custom field requires high privileges, and script execution requires another user to view the affected page; impact is limited to that user's browser context.

The record

CVE
CVE-2021-39117
Published
Aug 30, 2021
Updated
Oct 11, 2024
Vendor
Atlassian
Product
Jira Server
Classifications
CWE-79
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Aug 30, 2021CVE publishedPublication date reported by the CVE source.
  2. Oct 11, 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=unspecified <8.18.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Atlassian · Jira Serverversion=unspecified <8.18.0
Atlassian · Jira Data Centerversion=unspecified <8.18.0

Published CVSS scores

4.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:N
3.5NIST NVDAV:N/AC:M/Au:S/C:N/I:P/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
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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