CVE-2026-42796 json
Arelle < 2.39.10 Unauthenticated RCE via /rest/configure
published 2026-05-04 6 mo ago modified 2026-11-08 25 h ago also EUVD-2026-27079
- cvss
- 9.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 2.7%
- EPSS 2.7% chance of exploitation in 30 days, percentile 86%
- public exploits
- 0
- none known, plus a Nuclei check
Summary
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.
Patch / fix
- Arelle Arelle 2.39.10
- github.com/Arelle/Arelle#2320 pull request
- github.com/Arelle/Arelle/releases/tag/2.39.10 release
CISA SSVC
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
- Assessed
- 6 mo ago
Exploit prediction
2.75% chance of exploitation in the next 30 days, higher than 86% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- Nuclei template Arelle < 2.39.10 - Remote Code Execution nuclei detection template
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 9.2 | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N |
| CNA | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| CNA | 4.0 | 9.2 | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- Arelle Arelle
Classification
- Weakness
-
- CWE-306 Missing Authentication for Critical Functionality
References
-
github.com
/Arelle/Arelle/releases/tag/2.39.10
release-notes, patch
-
github.com
/Arelle/Arelle/pull/2320
issue-tracking, patch
-
vulncheck.com
/advisories/arelle-unauthenticated-rce-via-rest-configure
third-party-advisory
Sources
- CVE List CVE-2026-42796
- NVD CVE-2026-42796
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