CVE-2026-45558

CVE-2026-45558: critical vulnerability affecting the affected product. Check CVSS, KEV status, business impact and recommended administrator actions.
CVE-2026-45558CVSS 9.9Web

CVE-2026-45558

CVE-2026-45558: critical vulnerability affecting the affected product. Check CVSS, KEV status, business impact and recommended administrator actions.

CVSS
9.9 CRITICAL
EPSS
35.91%
Known exploited
not in KEV
Product
-

What is known

Roxy-WI is a web interface for managing Haproxy, Nginx, Apache and Keepalived servers. In versions 8.2.6.4 and prior, the HAProxy section-save endpoints (POST /api/service/haproxy/<server_id>/section/<section_type> and the PUT / global / defaults variants) accept a JSON option field that is not validated, not escaped, and is rendered verbatim into the generated HAProxy configuration via the section.j2, global.j2, and defaults.j2 Ansible templates. Because Roxy-WI then pushes the generated config to the load balancer and runs systemctl reload haproxy, an authenticated user with role ≤ 3 (user) can inject arbitrary HAProxy directives into the config that runs on every load balancer their group manages — including option external-check + external-check command /bin/bash -c '…', which gives remote code execution on the load balancer as the haproxy user on every health-check tick. At time of publication, there are no publicly available patches.

Business impact

Successful exploitation of CVE-2026-45558, a critical vulnerability (CVSS 9.9) affecting the affected product, may affect the confidentiality, integrity or availability of the vulnerable environment. The exact impact depends on the installed version, exposed interfaces and deployment configuration.

Recommended administrator action

Confirm whether the affected product is present and compare installed versions with the vendor advisory and NVD record. Apply the vendor patch or documented mitigation; until remediation is complete, reduce exposure of affected interfaces, review relevant logs and monitor for indicators of exploitation. DataHouse can support version verification, managed patching, network exposure reduction, log review and backup validation for dedicated, cloud and colocated environments.

Sources

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