What’s Vulnerable › Vulnerabilities

CVE-2026-42796: Arelle < 2.39.10 Unauthenticated RCE via /rest/configure

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 2.7% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-05-04 · updated 2026-06-17
• Weakness: CWE-306

Description

Arelle before 2.39.10 contains an unauthenticated remote code execution vulnerability in the /rest/configure REST endpoint that accepts a plugins query parameter and forwards it to the plugin manager without authentication or authorization. Attackers can supply a URL to a malicious Python file through the plugins parameter, causing the Arelle webserver to download and execute the attacker-controlled code within the Arelle process with its privileges.

Affected products

• Arelle: before 2.39.10 — fixed in 2.39.10

How to fix

Upgrade to a fixed version: Arelle 2.39.10. Check the vendor advisory for mitigations.

References

• https://github.com/Arelle/Arelle/pull/2320
• https://github.com/Arelle/Arelle/releases/tag/2.39.10
• https://www.vulncheck.com/advisories/arelle-unauthenticated-rce-via-rest-configure

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