How severe is CVE-2021-26085?

CVE-2021-26085 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2021-26085 being actively exploited?

Yes. CVE-2021-26085 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-03-28, which means active exploitation has been confirmed. It should be prioritised for remediation.

What products are affected by CVE-2021-26085?

CVE-2021-26085 primarily affects Atlassian Confluence Data Center. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-26085?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.

Does CVE-2021-26085 have an EU (EUVD) identifier?

Yes. CVE-2021-26085 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-12906. It is also flagged as exploited in the EUVD (since 2022-03-28).

When was CVE-2021-26085 published?

CVE-2021-26085 was published on 2021-08-03 and last updated on 2026-06-17.

CVE-2021-26085

CVE-2021-26085 is a medium-severity vulnerability in Atlassian Confluence Data Center with a CVSS 3.x base score of 5.3. It is listed in CISA's Known Exploited Vulnerabilities (KEV) catalog, confirming it has been exploited in the wild (added 2022-03-28). The underlying weakness is classified as CWE-425.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
CVSS v2: 5.0
EPSS exploit prediction: 100% (100th percentile)
Actively exploited: Yes — listed in CISA KEV (added 2022-03-28)
EU (EUVD) id: EUVD-2021-12906
EU exploitation: Flagged exploited in the ENISA EU Vulnerability Database (since 2022-03-28)
Weakness: CWE-425
Affected product: Atlassian Confluence Data Center
Published: 2021-08-03
Last modified: 2026-06-17

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

Frequently asked questions

What is CVE-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.
How severe is CVE-2021-26085?: CVE-2021-26085 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2021-26085 being actively exploited?: Yes. CVE-2021-26085 is on CISA's Known Exploited Vulnerabilities (KEV) catalog, added on 2022-03-28, which means active exploitation has been confirmed. It should be prioritised for remediation.
What products are affected by CVE-2021-26085?: CVE-2021-26085 primarily affects Atlassian Confluence Data Center. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-26085?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Because this CVE is known to be actively exploited, treat remediation as urgent — CISA KEV typically sets a short remediation deadline.
Does CVE-2021-26085 have an EU (EUVD) identifier?: Yes. CVE-2021-26085 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-12906. It is also flagged as exploited in the EUVD (since 2022-03-28).
When was CVE-2021-26085 published?: CVE-2021-26085 was published on 2021-08-03 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:atlassian:confluence_data_center:*:*:*:*:*:*:*:*
cpe:2.3:a:atlassian:confluence_server:*:*:*:*:*:*:*:*

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