Atlassian products hit by arbitrary file access flaw
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CERT-FR warns of multiple Atlassian Data Center vulnerabilities, led by CVE-2026-21589, allowing attackers to read sensitive data.
CERT-FR has issued an advisory covering multiple vulnerabilities affecting a wide range of Atlassian Data Center products, including Bamboo, Bitbucket, Confluence, Crowd, Crucible, Fisheye, and Jira Software. The primary vulnerability, CVE-2026-21589, is described by Atlassian as an arbitrary file access issue impacting multiple products, allowing an attacker to compromise the confidentiality of data. The advisory also references several older CVEs (dating back to 2019) that are bundled into this bulletin, likely as part of a consolidated patch cycle or dependency update.
Affected version ranges are extensive and product-specific, spanning numerous Data Center releases across Bamboo, Bitbucket, Confluence, Crowd, and Jira Software, as well as standalone Crucible and Fisheye installations. Defenders running any of these products should consult the official Atlassian security bulletin to identify exact affected and fixed versions for their deployment and apply patches accordingly.
No detail is provided in the CERT-FR advisory regarding active exploitation in the wild; the bulletin is a standard vulnerability notification urging patching. Given the breadth of affected products and the confidentiality impact, organizations running on-premises Atlassian Data Center products should prioritize patching, particularly for internet-facing or sensitive instances, and review Atlassian's bulletin for authentication and privilege requirements of the new CVE-2026-21589.
Mentioned in this report
Source reporting: https://www.cert.ssi.gouv.fr/avis/CERTFR-2026-AVI-1264
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