CVE-2026-21577

mediumpriority · track · 26EPSS 0.004 · 37 %ileDEEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.43% (37th) EPSS

CVSS 6.5 · medium

Is it mine?

31 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · cert_bund

EPSS · scored 2026-10-27

This High severity DoS (Denial of Service) vulnerability was introduced in versions 9.0.1, 9.1.0, 9.2.0, 9.3.1, 9.4.0, 9.5.1, 10.0.2, 10.1.0 and 10.2.0 of Confluence Data Center. This DoS (Denial of Service) vulnerability, with a CVSS Score of 7.1, allows an authenticated 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 9.2: Upgrade to a release greater than or equal to 9.2.17 Confluence Data Center 10.2: Upgrade to a release greater than or equal to 10.2.7 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 Penetration Testing program.

cvss

Technical severity, 0–10. One row per scoring source.

7.1

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 4.9–7.1

v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 2.8 · impact 3.6

v4.07.1highCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:Nsecondary · ENISA EU

v4.07.1highCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · security@atlassian.com

v4.04.9mediumCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:Xsecondary · CVSS-BT (t0sche)

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Trackcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-400US

affected products (31)

Products and version ranges known to be affected.

Oracle Linuxall versionscert_bundDEcpe:/o:oracle:linux:-
Red Hat Enterprise Linuxall versionscert_bundDEcpe:/o:redhat:enterprise_linux:-
Atlassian Bamboo≤ LTS <10.2.21cert_bundDE
Atlassian Bamboo≤ LTS <12.1.9cert_bundDE
Atlassian Bitbucket≤ LTS <10.3.2cert_bundDE
Atlassian Bitbucket≤ LTS <9.4.22cert_bundDE
Atlassian Confluence≤ LTS <10.2.14cert_bundDE
Atlassian Confluence≤ LTS <9.2.22cert_bundDE
Atlassian Crucible< 4.9.12cert_bundDE
Atlassian Fisheye< 4.9.12cert_bundDE
Atlassian Jira≤ LTS <11.3.8cert_bundDE
Atlassian Jira≤ LTS <10.3.23cert_bundDE
Dell Secure Connect Gateway< 5.36.00.16cert_bundDE
Atlassian Confluence Data Center≤ 9.1.0 to 9.1.1enisa_euvdEU
Atlassian Confluence Data Center≤ 9.0.1 to 9.0.3enisa_euvdEU
Atlassian Confluence Data Center≤ 10.2.0 to 10.2.6enisa_euvdEU
Atlassian Confluence Data Center≤ 10.1.0 to 10.1.2enisa_euvdEU
Atlassian Confluence Data Center≤ 9.2.0 to 9.2.15enisa_euvdEU
Atlassian Confluence Data Center≤ 10.0.2 to 10.0.3enisa_euvdEU
Atlassian Confluence Data Center≤ 9.5.1 to 9.5.4enisa_euvdEU

showing 20 of 31

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2026-2460Atlassian Bamboo, Bitbucket, Confluence, Fisheye, Crucible, Jira und Jira Service Management: Mehrere SchwachstellenDeutsch2026-07-21csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Atlassian Bamboo, Bitbucket, Confluence, Fisheye, Crucible, Jira und Jira Service Management ausnutzen, um beliebigen Code auszuführen, erweiterte Berechtigungen zu erlangen, Sicherheitsmaßnahmen zu umgehen, Daten zu manipulieren, vertrauliche Informationen offenzulegen oder einen Denial-of-Service-Zustand auszulösen.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund NVD CVE.org MITRE

published 2026-07-21modified 2026-10-24

references (6)

External citations — patches, advisories, analysis.

scry

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