CVE-2026-19670

Malcolm's nginx Lua role-based access control (RBAC) layer decides whether an authenticated user may reach a role-restricted path (e.g. /htadmin, /auth, /admin_login, /arkime/api/esadmin, NetBox, upload endpoints) by pattern-matching the raw, percent-encoded request URI. Nginx itself, however, selects which location block actually serves the request using the percent-decoded, normalized URI. Because the RBAC check never percent-decodes its input, an authenticated low-privilege user can request an admin-only path using percent-encoding (e.g. /%68tadmin.php) and have nginx route it to the restricted location while the Lua RBAC gate evaluating the un-decoded raw string finds no matching restriction and grants access.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/cisagov/Malcolm/security/advisories/GHSA-f2v6-8cj4-mhr6
https://www.cisa.gov/news-events/ics-advisories/icsa-26-230-01
https://github.com/cisagov/Malcolm/security/advisories/GHSA-f2v6-8cj4-mhr6

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-18 20:17

Updated : 2026-09-08 15:28

NVD link : CVE-2026-19670

Mitre link : CVE-2026-19670

CVE.ORG link : CVE-2026-19670

JSON object : View

Products Affected

No product.

CWE

CWE-863

Incorrect Authorization

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