CVE-2021-26086

Status: AnalyzedMedium (5.3)⚠ Active exploitation

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.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Base score: 5.3

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 100%
Percentile among all scored CVEs: 100
Score date: 9/29/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

CISA KEV — actively exploited

Added to catalog: 11/12/2024
Remediation due date: 12/3/2024
Known ransomware use: Unknown

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1190 Exploit Public-Facing Applicationinitial access90 %
Primary impactT1005 Data from Local Systemcollection85 %

CVE de path traversal (CWE-22) en endpoint web expuesto, sin autenticación (PR:N, UI:N), permite lectura de archivos /WEB-INF/web.xml. Explotación remota típica de aplicación expuesta.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Vulnerability Scanning Privileged Account Management Network Segmentation Limit Access to Resource Over Network Filter Network Traffic Application Isolation and Sandboxing

Affected technologies (2)

Atlassian — Jira Data Center Atlassian — Jira Server

CWEs

CWE-22
CWE-22

References

Raw JSON (NVD)

Show

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