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CVE PROGRAM SOURCE RECORD7.1 High

CVE-2026-63177

Malcolm Vulnerable to Authorization Bypass via URI Normalization Differential in Nginx Lua RBAC

Description

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.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

cisagov Malcolm

Default version status: unaffected

  • < 26.07.0affected
  • 26.07.0unaffected

References