CVE-2021-26076

Severity: low (CVSS 3.7 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-04-15 · updated 2026-06-17

Description

The jira.editor.user.mode cookie set by the Jira Editor Plugin in Jira Server and Data Center before version 8.5.12, from version 8.6.0 before version 8.13.4, and from version 8.14.0 before version 8.15.0 allows remote anonymous attackers who can perform an attacker in the middle attack to learn which mode a user is editing in due to the cookie not being set with a secure attribute if Jira was configured to use https.

Affected products

Atlassian Data Center: before 8.5.12 — fixed in 8.5.12
Atlassian Jira: before 8.5.12 — fixed in 8.5.12
Atlassian Jira: from 8.6.0 before 8.13.4; from 8.14.0 before 8.15.1 — fixed in 8.13.4, 8.15.1
Atlassian Jira: from 8.6.0 before 8.13.4; from 8.14.0 before 8.15.1 — fixed in 8.13.4, 8.15.1

How to fix

Upgrade to a fixed version: Atlassian Data Center 8.5.12; Atlassian Jira 8.5.12; Atlassian Jira 8.13.4, 8.15.1; Atlassian Jira 8.13.4, 8.15.1. Check the vendor advisory for mitigations.

References

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