CVE-2021-43942
Affected versions of Atlassian Jira Server and Data Center allow remote attackers to inject arbitrary HTML or JavaScript via a Reflected Cross-Site Scripting (XSS) vulnerability in the /rest/collectors/1.0/template/custom endpoint.
Does this matter?
EPSS puts the probability of exploitation in the next 30 days at 55.4%, higher than 99% of all known CVEs. Patch or mitigate before the next change window.
Description
Affected versions of Atlassian Jira Server and Data Center allow remote attackers to inject arbitrary HTML or JavaScript via a Reflected Cross-Site Scripting (XSS) vulnerability in the /rest/collectors/1.0/template/custom endpoint. To exploit this issue, the attacker must trick a user into visiting a malicious website. The affected versions are before version 8.13.15, and from version 8.14.0 before 8.20.3.
- CVSS 3.1
- 6.1 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
- EPSS
- 55.36% probability · 99th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-79
- Affected
- atlassian/jira server · atlassian/jira server and data center
- Source
- security@atlassian.com
EPSS 55.4% since 3 November 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://jira.atlassian.com/browse/JRASERVER-73068Issue Tracking, Vendor Advisory
- https://jira.atlassian.com/browse/JRASERVER-73068Issue Tracking, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.