CVE-2021-26086 Atlassian Jira Server and Data Center Path Traversal Vulnerability
Atlassian Jira Server and Data Center contain a path traversal vulnerability that allows a remote attacker to read particular files in the /WEB-INF/web.xml endpoint.
From the CISA KEV catalogue version 2026.11.06, with Cybergen analysis. Updated 6 Nov 2026.
Should You Worry?
- CISA confirmed exploitation in the wild and added it to the Known Exploited Vulnerabilities catalogue on 12 Nov 2024.
- Rated Medium severity (CVSS 5.3, scored by CISA).
- This product type is often exposed to the internet, which is where attackers scan for it first.
- It has been in the catalogue for 724 days. Systems still unpatched now have almost certainly been scanned for it.
What It Is
Affected versions of Atlassian Jira Server and Data Center allow remote attackers to read particular files via a path traversal vulnerability in the /WEB-INF/web.xml endpoint. The affected versions are before version 8.5.14, from version 8.6.0 before 8.13.6, and from version 8.14.0 before 8.16.1.
Affected Versions
| Product | Versions |
|---|---|
| Atlassian Jira Server | unspecified to before 8.5.14 8.6.0 to before unspecified unspecified to before 8.13.6 8.14.0 to before unspecified unspecified to before 8.16.1 |
| Atlassian Jira Data Center | unspecified to before 8.5.14 8.6.0 to before unspecified unspecified to before 8.13.6 8.14.0 to before unspecified unspecified to before 8.16.1 |
From the public CVE record, as supplied by the vendor. Always confirm against the vendor advisory.
What To Do Now
- 1
Find it
Search your asset inventory and external attack surface for Atlassian Jira Server and Data Center. Include cloud images, appliances and anything a supplier runs for you.
Attack Surface Management - 2
Fix it
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Vulnerability Management - 3
Hunt for compromise
If an affected system was reachable before you patched, assume it may have been hit. Check logs, new accounts, web shells and outbound connections from the date of exposure.
Incident Response - 4
Prove it is fixed
Rescan or test the system after patching. Upgrades that fail silently and forgotten secondary instances are common.
Penetration Testing
The Compliance Clock
General guidance, not legal advice. Your obligations depend on your sector, scope and jurisdiction.
Not Sure If You Are Exposed?
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