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Vulnerabilities

Vulnerability · CVE-2021-26085

Atlassian Confluence Server Pre-Authorization Arbitrary File Read Vulnerability

Published Aug 2, 2021 · catalog updated Jun 16, 2026 · Atlassian Confluence Server and Data Center

Patch now

CVE-2021-26085 is in the CISA known-exploited catalog, due Apr 18, 2022. Confirm Atlassian Confluence Server and Data Center against the vendor advisory and apply that fix. The CVSS score does not change the priority.

Gaps on this record

  • No version range is stored. A customer cannot check an installed version against this record.
Severity
Medium5.3
Known exploitation
CISA KEV and VulnCheck KEV
EPSS
99.94%
Remediation
Remediation guidance
Affected products
cpe atlassian/confluence data center · cpe atlassian/confluence server · vendor Atlassian Confluence Server · vendor Atlassian Confluence Server and Data Center

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.

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • cpe atlassian/confluence data centerversion unspecified
  • cpe atlassian/confluence serverversion unspecified
  • vendor Atlassian Confluence Serverversion unspecified
  • vendor Atlassian Confluence Server and Data Centerversion unspecified

How to fix CVE-2021-26085

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

CVE-2021-26085 is in the CISA known-exploited catalog, due Apr 18, 2022. Confirm Atlassian Confluence Server and Data Center against the vendor advisory and apply that fix. The CVSS score does not change the priority.

Which versions are affected?

Affected version ranges are not on this record. Apply updates per vendor instructions.

What should an analyst verify?

CWE-425: Direct Request (Forced Browsing). EPSS 99.94%. The CISA KEV listing is the exploitation evidence. A public exploit reference is linked in Sources. That is not the same as confirmed exploitation. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. Aug 2, 2021 · Catalog

    Detected

    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.

  2. Mar 28, 2022 · CISA KEV

    Known exploited

    Apply updates per vendor instructions.

  3. Apr 18, 2022 · CISA KEV

    Remediation due

    Apply updates per vendor instructions.

  4. Jun 16, 2026 · Catalog

    Updated

    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.

Sources

  • CISA KEVConfirmed exploitationCVE-2021-26085

    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.

    cisa.gov
  • CVE.orgVulnerability recordCVE-2021-26085

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2021-26085

    30-day exploitation probability 99.9%

    first.org
  • Exploit DatabasePublic exploit reference50377

    Public archive entry. The exploit body is not stored here.

    exploit-db.com
  • NIST NVDVulnerability recordCVE-2021-26085

    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.

    nvd.nist.gov
  • Packet Storm SecurityCited referencehttp://packetstormsecurity.com/files/164401/Atlassian-Confluence-Server-7.5.1-Arbitrary-File-Read.html

    Packet Storm link already published on the finding.

    packetstormsecurity.com
  • VulnCheck KEVConfirmed exploitationCVE-2021-26085

    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.

    vulncheck.com

References

Freshness

Last verified in this catalog Oct 17, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.