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CVE-2021-26086

Atlassian Jira Server and Data Center Path Traversal

5.3 MEDIUMActively exploited (CISA KEV)Public exploitEPSS 100.0%
  1. Published15 Aug 2021
  2. Added to CISA KEV12 Nov 2024
  3. Remediation due3 Dec 2024
Actively exploited (CISA KEV)

Atlassian Jira Server and Data Center contain a path traversal vulnerability that allows a remote attacker to read particular files in the /WEB-INF/web.xml endpoint.

Added to KEV: 12 Nov 2024Federal remediation due: 3 Dec 2024

Description

Affected versions of Atlassian Jira Server and Data Center allow remote attackers to read particular files via a path traversal vulnerability in the /WEB-INF/web.xml endpoint. The affected versions are before version 8.5.14, from version 8.6.0 before 8.13.6, and from version 8.14.0 before 8.16.1.

CVSS 3.1 breakdown

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
ScopeUnchanged
ConfidentialityLow
IntegrityNone
AvailabilityNone
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Affected products

Atlassian Jira Data Center≥ 8.14.0 < 8.16.1 · ≥ 8.6.0 < 8.13.6 · < 8.5.14
Atlassian Jira Server≥ 8.14.0 < 8.16.1 · ≥ 8.6.0 < 8.13.6 · < 8.5.14

Remediation

Fixed in
Atlassian Jira Data Center≥ 8.16.1
Atlassian Jira Server≥ 8.16.1

References

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Frequently asked

Is CVE-2021-26086 being actively exploited?

Yes. CVE-2021-26086 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added 12 Nov 2024.

How severe is CVE-2021-26086?

CVE-2021-26086 has a CVSS 3.1 base score of 5.3, rated medium. EPSS estimates a 100.0% probability of exploitation.

Which products are affected by CVE-2021-26086?

Affected products include Atlassian Jira Data Center, Atlassian Jira Server.

How do I fix CVE-2021-26086?

Upgrade affected software to a fixed version, for example Atlassian Jira Data Center 8.16.1, Atlassian Jira Server 8.16.1 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2021-26086 against the real software inventory on every managed device, as each hourly inventory arrives. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. Because it is on the CISA KEV list, a risk for it never ranks below high, and the update that fixes it moves to the Emergency patch lane. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.