How severe is CVE-2025-22166?

CVE-2025-22166 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2025-22166 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-22166?

CVE-2025-22166 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-2025-22166?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

Does CVE-2025-22166 have an EU (EUVD) identifier?

Yes. CVE-2025-22166 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-35185.

When was CVE-2025-22166 published?

CVE-2025-22166 was published on 2025-10-21 and last updated on 2026-06-17.

CVE-2025-22166

CVE-2025-22166 is a high-severity vulnerability in Atlassian Confluence Data Center with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-405.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v4: 8.3
EPSS exploit prediction: 0% (37th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-35185
Weakness: CWE-405
Affected product: Atlassian Confluence Data Center
Published: 2025-10-21
Last modified: 2026-06-17

Description

This High severity DoS (Denial of Service) vulnerability was introduced in version 2.0 of Confluence Data Center. This DoS (Denial of Service) vulnerability, with a CVSS Score of 8.3, allows an attacker to cause a resource to be unavailable for its intended users by temporarily or indefinitely disrupting services of a host connected to a network. Atlassian recommends that Confluence Data Center customers upgrade to latest version, if you are unable to do so, upgrade your instance to one of the specified supported fixed versions: Confluence Data Center and Server 8.5: Upgrade to a release greater than or equal to 8.5.25 Confluence Data Center and Server 9.2: Upgrade to a release greater than or equal to 9.2.7 Confluence Data Center and Server 10.0: Upgrade to a release greater than or equal to 10.0.2 See the release notes ([https://confluence.atlassian.com/doc/confluence-release-notes-327.html]). You can download the latest version of Confluence Data Center from the download center ([https://www.atlassian.com/software/confluence/download-archives]). This vulnerability was reported via our Atlassian (Internal) program.

Frequently asked questions

What is CVE-2025-22166?: This High severity DoS (Denial of Service) vulnerability was introduced in version 2.0 of Confluence Data Center. This DoS (Denial of Service) vulnerability, with a CVSS Score of 8.3, allows an attacker to cause a resource to be unavailable for its intended users by temporarily or indefinitely disrupting services of a host connected to a network. Atlassian recommends that Confluence Data Center customers upgrade to latest version, if you are unable to do so, upgrade your instance to one of the specified supported fixed versions: Confluence Data Center and Server 8.5: Upgrade to a release greater than or equal to 8.5.25 Confluence Data Center and Server 9.2: Upgrade to a release greater than or equal to 9.2.7 Confluence Data Center and Server 10.0: Upgrade to a release greater than or equal to 10.0.2 See the release notes ([https://confluence.atlassian.com/doc/confluence-release-notes-327.html]). You can download the latest version of Confluence Data Center from the download center ([https://www.atlassian.com/software/confluence/download-archives]). This vulnerability was reported via our Atlassian (Internal) program.
How severe is CVE-2025-22166?: CVE-2025-22166 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2025-22166 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-22166?: CVE-2025-22166 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-2025-22166?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2025-22166 have an EU (EUVD) identifier?: Yes. CVE-2025-22166 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-35185.
When was CVE-2025-22166 published?: CVE-2025-22166 was published on 2025-10-21 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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