PatchTheCVECVE-2026-42796: Arelle before 2.39.10 contains an unauthenticated remote code execution vulnerability in the /rest/configure R
CVE-2026-42796 is a critical-severity flaw (CVSS 9.8) affecting arelle. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
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 privile
Why this priority
- Critical severity
- CISA SSVC: automatable with total technical impact
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 9.8 (Critical) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 2.7% (top 14%) |
| CISA exploited list | No |
| Weakness | CWE-306 |
| Published | 2026-05-04 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Exact fixes by distribution
Public exploits and detection
Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.
- GitHub PoC: ameerhamza-malik/CVE-2026-42796 (0 stars)
- Nuclei scan template: Arelle < 2.39.10 - Remote Code Execution
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-42796?
arelle: upgrade to 2.39.10. Exact commands for each OS are on this page.
Is CVE-2026-42796 being exploited?
CVE-2026-42796 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-42796 affect?
CVE-2026-42796 affects arelle. Severity is critical (CVSS 9.8). 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.
How urgent is CVE-2026-42796?
Priority 64/100. Critical severity; CISA SSVC: automatable with total technical impact; Remotely exploitable, no login, no user action