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.
- Vendor
- Atlassian
- Product
- Jira Server and Data Center
- CVSS
- 5.3
- EPSS (exploit probability)
- 100.0%
- Status
- kev
- CISA patch-by (BOD 22-01)
- Added to KEV
Is CVE-2021-26086 being exploited?
Yes. CISA added CVE-2021-26086 to its Known Exploited Vulnerabilities catalog on . CISA only lists a CVE when it has reliable evidence of exploitation in the wild.
FIRST's EPSS model puts the probability of exploitation activity in the next 30 days at 100.0% (scored October 14, 2026).
- CISA KEV[ LISTED ]
- ENISA EUVD (exploited)[ — ]
- CIRCL KEV[ — ]
Catalog snapshot 2026-11-13. Full cross-catalog view: /kev-comparison
CVE-2021-26086 timeline
Every event links to its source. Catalog dates are each catalog's own; day offsets count from NVD publication. Data: JSON
What to do
CISA required actionApply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
US federal civilian agencies must remediate by (21 days after listing) under BOD 22-01. Everyone else: that deadline is a sensible upper bound, not a target. Vendor guidance and the NVD record are linked under Source above.
Other Atlassian CVEs we track
| CVE / Vulnerability | Severity | CVSS | EPSS | Added to KEV |
|---|---|---|---|---|
| CVE-2026-21589 Path traversal allows unauthenticated file read in eight Atlassian Data Center productswrite-up | [ CRITICAL ] | 9.3 | 99.7% | |
| CVE-2023-22527 Atlassian Confluence Data Center and Server Template Injection Vulnerabilityransomware use | [ CRITICAL ] | 9.8 | 100.0% | |
| CVE-2023-22518 Atlassian Confluence Data Center and Server Improper Authorization Vulnerabilityransomware use | [ CRITICAL ] | 9.8 | 100.0% | |
| CVE-2023-22515 Atlassian Confluence Data Center and Server Broken Access Controlransomware usewrite-up | [ CRITICAL ] | 9.8 | 99.2% | |
| CVE-2022-36804 Atlassian Bitbucket Server and Data Center Command Injection Vulnerability | [ HIGH ] | 8.8 | 99.0% | |
| CVE-2022-26138 Atlassian Questions For Confluence App Hard-coded Credentials Vulnerability | [ CRITICAL ] | 9.8 | 98.2% | |
| CVE-2022-26134 Atlassian Confluence OGNL Injection Remote Code Executionransomware usewrite-up | [ CRITICAL ] | 9.8 | 100.0% | |
| CVE-2021-26085 Atlassian Confluence Server Pre-Authorization Arbitrary File Read Vulnerabilityransomware use | [ MEDIUM ] | 5.3 | 99.9% |