CVE-2026-63177 (GCVE-0-2026-63177)
Vulnerability from cvelistv5 – Published: 2026-08-11 20:30 – Updated: 2026-10-02 20:27
VLAI
EPSS
VEX
Title
Malcolm Vulnerable to Authorization Bypass via URI Normalization Differential in Nginx Lua RBAC
Summary
Malcolm is a network traffic analysis tool suite. Prior to version 26.07.0, role-based access control enforced in the Nginx OpenResty Lua layer evaluates the raw, unnormalized `ngx.var.request_uri`, while Nginx itself routes requests using the normalized path. An authenticated low-privilege user can prepend a traversal segment (for example `/x/../upload/...`) so that Nginx routes the request to a restricted backend while the Lua role check fails to match any rule and falls open, granting access it should deny. Version 26.07.0 fixes the issue.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-12 22:07 UTC
CWE
- CWE-863 - Incorrect Authorization
Assigner
References
4 references
Impacted products
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