CVE-2021-26085Known exploitationPublic exploitNetwork attack vector

Unauthenticated file read via improper resource validation

Published Aug 3, 2021 · Updated Oct 21, 2025

Arbitrary file read in Atlassian Confluence before 7.4.10 and 7.5.0 through 7.12.2 allows remote attackers to view restricted resources. The /s/ static-resource handler improperly validates crafted resource paths containing a semicolon, allowing requests to reach files under protected WEB-INF paths. No authentication or user interaction is required, and exposed content is limited to files readable by the Confluence process.

CVSS severity5.3
Medium
EPSS probability99.94%
Next 30 days · Sep 16, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Arbitrary file read in Atlassian Confluence before 7.4.10 and 7.5.0 through 7.12.2 allows remote attackers to view restricted resources. The /s/ static-resource handler improperly validates crafted resource paths containing a semicolon, allowing requests to reach files under protected WEB-INF paths. No authentication or user interaction is required, and exposed content is limited to files readable by the Confluence process.

The record

CVE
CVE-2021-26085
Published
Aug 3, 2021
Updated
Oct 21, 2025
Vendor
Atlassian
Product
Confluence Data Center
Classifications
CWE-425, T1213.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 3, 2021CVE publishedPublication date reported by the CVE source.
  2. Oct 21, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=7.5.0 <unspecified
  2. Affected versionversion=unspecified <7.12.3
  3. Affected versionversion=unspecified <7.4.10

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Atlassian · Confluence Data Centerversion=7.5.0 <unspecified; version=unspecified <7.12.3; version=unspecified <7.4.10
Atlassian · Confluence Serverversion=7.5.0 <unspecified; version=unspecified <7.12.3; version=unspecified <7.4.10

Published CVSS scores

5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationReported
Public exploitPublished

Weakness, pattern, technique

CWE-425Direct Request ('Forced Browsing')
T1213.001Confluence

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Reported exploitation

Technologies

Your stack

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Your stack

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