CVE-2025-34027 Versa Concerto Authentication Bypass File Write Remote Code Execution
Unauthenticated attackers can bypass authentication and exploit a race condition to achieve remote code execution on Versa Concerto SD-WAN platforms.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-34027?
CVE-2025-34027 is a critical authentication bypass vulnerability in Versa Concerto, published on 21 May 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official 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.
Weakness: CWE-367
Which versions are affected by CVE-2025-34027?
It affects 1 product.
Products include Versa-Networks Concerto.
How do I fix CVE-2025-34027?
No fix has been published for CVE-2025-34027 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2025-34027 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-34027 exists.
Public exploit code: 1 Nuclei template.
Other vulnerabilities in Versa Concerto
Sources
Also known as GHSA-96gf-3rqf-c8m9.