What is CVE-2026-42796?

CVE-2026-42796 is a critical-severity vulnerability in Arelle, classified under Missing Authentication for Critical Function. CVSS score: 9.8/10. Published 2026-05-04.

How severe is CVE-2026-42796?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Is CVE-2026-42796 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Auth bypass in Arelle

CVE-2026-42796

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…

Vulnerability class: Broken Authentication

EPSS: 0.005 (65.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

Affected products

Arelle — versions 0
Workiva Arelle

Weakness classification (CWE)

CWE-306 — Missing Authentication for Critical Function

Public proof-of-concept exploits

ameerhamza-malik/CVE-2026-42796

References

disclosure@vulncheck.com (release-notes, Release Notes, patch)
disclosure@vulncheck.com (issue-tracking, Patch, Issue Tracking)
disclosure@vulncheck.com (Third Party Advisory, third-party-advisory)

Frequently asked questions

What is CVE-2026-42796?: CVE-2026-42796 is a critical-severity vulnerability in Arelle, classified under Missing Authentication for Critical Function. CVSS score: 9.8/10. Published 2026-05-04.
How severe is CVE-2026-42796?: Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2026-42796 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.