CVE-2025-34027 (GCVE-0-2025-34027)
Vulnerability from cvelistv5 – Published: 2025-05-21 21:58 – Updated: 2026-02-26 18:27
VLAI
EPSS
VEX
Title
Versa Concerto Authentication Bypass File Write Remote Code Execution
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-05-28 03:56 UTC
CWE
- CWE-367 - Time-of-check Time-of-use (TOCTOU) Race Condition
Assigner
VulnCheck
CNA
References
1 reference
| URL | Tags |
|---|---|
| https://projectdiscovery.io/blog/versa-concerto-a… | exploitmitigation |
Impacted products
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Sightings
| Author | Source | Type | Date | Other |
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Nomenclature
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
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Browse all ATT&CK techniques and the vulnerabilities related to each.
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