Description
The Versa Concerto SD-WAN orchestration platform is vulnerable to an authentication bypass in the Traefik reverse proxy configuration, allowing at attacker to access administrative endpoints. The Spack upload endpoint can be leveraged for a Time-of-Check to Time-of-Use (TOCTOU) write in combination with a race condition to achieve remote code execution via path loading manipulation, allowing an unauthenticated actor to achieve remote code execution (RCE).This issue is known to affect Concerto from 12.1.2 through 12.2.0. Additional versions may be vulnerable.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Versa | Concerto | 12.1.2 – ≤ 12.2.0 | — |
Automated scanner template
A ready-made Nuclei template detects this vulnerability automatically. Vulnerabilities with public scanner templates are typically probed across the internet soon after the template appears — exposed systems should be patched first.
- Versa Concerto API Path Based - Authentication Bypass http/cves/2025/CVE-2025-34027.yaml
Source: projectdiscovery/nuclei-templates (MIT) — updated daily. Only links are listed.
References
- https://projectdiscovery.io/blog/versa-concerto-authentication-bypass-rce exploit mitigation