---
id: "CVE-2021-26085"
kind: "vulnerability"
aliases: ["CVE-2021-26085"]
title: "Atlassian Confluence Server: Atlassian Confluence Server Pre-Authorization Arbitrary File Read Vulnerability"
severity: "high"
cvss: 5.3
epss: 0.99937
exploited: true
status: "open"
category: "package"
products: [{"name": "Atlassian Confluence Server", "fixed": [], "affected": "", "ecosystem": "vendor"}]
ecosystems: ["vendor"]
tags: ["atlassian", "confluence", "exploited", "package", "ransomware", "self-hosted"]
not_affected_if: ["atlassian-cloud", "managed-hosting"]
published_at: "2021-08-03T00:15:08+00:00"
first_seen_at: "2026-10-23T19:11:52+00:00"
updated_at: "2026-10-23T21:57:35+00:00"
sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2021-26085", "first_seen_at": "2026-10-23T19:11:52+00:00"}, {"source": "epss", "url": "https://api.first.org/data/v1/epss?cve=CVE-2021-26085", "first_seen_at": "2026-10-23T19:13:44+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-26085", "first_seen_at": "2026-10-23T21:57:35+00:00"}]
---

# Atlassian Confluence Server: Atlassian Confluence Server Pre-Authorization Arbitrary File Read Vulnerability

Atlassian Confluence Server has a pre-authorization arbitrary file read flaw in its /s/ endpoint, so remote attackers can view restricted files without logging in. It is listed as actively exploited in the wild and tagged as used in ransomware campaigns.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:Atlassian Confluence Server affected ? fixed ?

## Fix

Apply the Atlassian vendor update for Confluence Server per vendor instructions; the sources do not name the fixed version.

## Timeline

- 2026-10-23T19:11:52+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2021-26085
- 2026-10-23T19:13:44+00:00 epss https://api.first.org/data/v1/epss?cve=CVE-2021-26085
- 2026-10-23T21:57:35+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2021-26085

## From the sources

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. The affected versions are before version 7.4.10, and from version 7.5.0 before 7.12.3.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_