CVE-2019-20102

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-04-22 · updated 2026-06-17
Weakness: CWE-79

Description

The attachment-uploading feature in Atlassian Confluence Server from version 6.14.0 through version 6.14.3, and version 6.15.0 before version 6.15.5 allows remote attackers to achieve stored cross-site- scripting (SXSS) via a malicious attachment with a modified `mimeType` parameter.

Affected products

Atlassian Confluence Data Center: from 6.14.0 through 6.14.3; from 6.15.0 before 6.15.5 — fixed in 6.15.5

How to fix

Upgrade to a fixed version: Atlassian Confluence Data Center 6.15.5. Check the vendor advisory for mitigations.

References

https://jira.atlassian.com/browse/CONFSERVER-59358
https://jira.atlassian.com/browse/CONFSERVER-59358

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