CVE-2021-26085 : Affected versions of Atlassian Confluence Server allow remote attackers to view restricted resources via a Pre-Authoriza

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.

Published 2021-08-03 00:15:09

Updated 2022-06-10 14:25:54

Source Atlassian

View at NVD, CVE.org

CVE-2021-26085 is in the CISA Known Exploited Vulnerabilities Catalog

This issue is known to have been leveraged as part of a ransomware campaign.

CISA vulnerability name:

Atlassian Confluence Server Pre-Authorization Arbitrary File Read Vulnerability

CISA required action:

Apply updates per vendor instructions.

CISA description:

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.

Added on 2022-03-28 Action due date 2022-04-18

Exploit prediction scoring system (EPSS) score for CVE-2021-26085

Probability of exploitation activity in the next 30 days: 96.32%

Percentile, the proportion of vulnerabilities that are scored at or less: ~ 100 % EPSS Score History EPSS FAQ

CVSS scores for CVE-2021-26085

Base Score	Base Severity	CVSS Vector	Exploitability Score	Impact Score	Score Source
5.0	MEDIUM	AV:N/AC:L/Au:N/C:P/I:N/A:N	10.0	2.9	NIST
Access Vector: Network Access Complexity: Low Authentication: None Confidentiality Impact: Partial Integrity Impact: None Availability Impact: None
5.3	MEDIUM	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N	3.9	1.4	NIST
Attack Vector: Network Attack Complexity: Low Privileges Required: None User Interaction: None Scope: Unchanged Confidentiality: Low Integrity: None Availability: None

CWE ids for CVE-2021-26085

CWE-862 Missing Authorization

The product does not perform an authorization check when an actor attempts to access a resource or perform an action.

Assigned by: nvd@nist.gov (Primary)

References for CVE-2021-26085

https://jira.atlassian.com/browse/CONFSERVER-67893

[CONFSERVER-67893] Pre-Authorization Arbitrary File Read in /s/ endpoint - CVE-2021-26085 - Create and track feature requests for Atlassian products.
Issue Tracking;Vendor Advisory
http://packetstormsecurity.com/files/164401/Atlassian-Confluence-Server-7.5.1-Arbitrary-File-Read.html

Atlassian Confluence Server 7.5.1 Arbitrary File Read ≈ Packet Storm
Exploit;Third Party Advisory;VDB Entry

Products affected by CVE-2021-26085