CVE-2021-26085

Atlassian Confluence Server — Atlassian Confluence Server Pre-Authorization Arbitrary File Read Vulnerability
⚠️ CVSS 3.1  5.3 / 10 — MEDIUM 🔴 CISA Known Exploited Vulnerability

Overview

Affected versions of Atlassian Confluence Server allow remote attackers to view restricted resources via a pre-authorization arbitrary file read vulnerability in the /s/ endpoint.

https://nvd.nist.gov/vuln/detail/CVE-2021-26085

Key Details

PropertyValue
CVE ID CVE-2021-26085
Vendor / Product Atlassian — Confluence Server
NVD Published2021-08-03
NVD Last Modified2025-10-24
CVSS 3.1 Score5.3
CVSS 3.1 VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
SeverityMEDIUM
CWE CWE-425
CISA KEV Added2022-03-28
CISA KEV Deadline2022-04-18
Known Ransomware Use ⚠️ Yes

CVSS 3.1 Breakdown

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
None

Required Action

CISA BOD 22-01 Deadline: 2022-04-18. Apply updates per vendor instructions.

Timeline

DateEvent
2022-03-28Added to CISA Known Exploited Vulnerabilities catalog
2022-04-18CISA BOD 22-01 remediation deadline

References

ResourceType
NVD — CVE-2021-26085 Vulnerability Database
CISA KEV Catalog Entry US Government