CVE-2026-107334
MediumCVSS 5.4Exploitation Probability (EPSS)
Low risk11th percentile - higher than 11% of all known CVEs
Summary
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.
Risk Assessment
An authenticated low-privilege user can gain access to administrative functions, potentially leading to system integrity compromise and unauthorized changes.
Recommendation
Update the RBAC logic to percent-decode before pattern matching. Additionally, enforce access control at the backend level, not only at the nginx level.
Other vulnerabilities in Malcolm
See all- CVE-2026-107361Medium
The Arkime live capture service (arkime-live) in Malcolm runs with network_mode: host, exposing port 8005 on all network interfaces (viewHost=0.0.0.0). Arkime trusts the X-Forwarded-User header from any IP address (userAuthIps=::,0.0.0.0/0) and auto-creates users with full access. The passwordSecret is hardcoded to the public value "Malcolm". A network-adjacent attacker bypasses nginx entirely by connecting directly to port 8005 with a forged identity header.
- CVE-2026-107336Medium
Malcolm's front nginx reverse proxy defines a "Dashboards → Arkime shortcut" location using a case-insensitive regex matcher but a case-sensitive rewrite. A request whose path segment is not exact-lowercase (for example /IDDASH2ARK/...) enters the location (the matcher fires) but evades the rewrite (no redirect is issued), so nginx falls through to the location's proxy_pass to the Arkime backend. That location is the one proxied location in the shipped config that does not include the per-location authentication file, so the request reaches Arkime unauthenticated. The same location also forwards a client-supplied X-Forwarded-User header un-overwritten, and Arkime is configured to trust X-Forwarded-User as the authenticated username — so an unauthenticated network caller can reach the Arkime backend while supplying a forged, auto-provisioned identity.
- CVE-2026-107335Medium
Malcolm's upload-processing pipeline (scripts/safe-extract.py) enforces entry-count, nesting-depth, and total-uncompressed-byte limits when extracting container archives (zip/tar/rar/7z via libarchive), but those limits are not applied when the uploaded file is a single-stream compressed format (.gz, .bz2, .xz, .lzma, .lz) that isn't a .tar.*-style archive. Any authenticated user permitted to upload PCAP/log files can upload a small, highly compressible file (e.g. a gzip bomb) that decompresses to an effectively unbounded size on disk, exhausting the shared Docker volume used by OpenSearch, Logstash, Arkime, and Zeek, and disrupting the platform for all users.
- CVE-2026-19671Medium
Malcolm's upload-processing pipeline enforces limits on container archives but not on single-stream compressed formats. An authenticated user can upload a small, highly compressible file that decompresses to an unbounded size, exhausting the shared Docker volume and disrupting the platform.
- CVE-2026-19670Medium
Malcolm's nginx Lua RBAC layer matches patterns against the raw, percent-encoded request URI, while nginx routes requests using the decoded URI. This allows an authenticated low-privilege user to access admin-only paths by percent-encoding the path, bypassing restrictions.
- CVE-2026-63177High
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.
- CVE-2026-63134Medium
Malcolm is a network traffic analysis tool suite. Prior to version 26.07.0, `safe-extract.py` protects file extraction with libarchive's secure flags, but creates directory entries with a raw `os.makedirs(os.path.join(dest, entry.pathname))` that has no traversal protection. An uploaded malicious archive containing a directory entry with a `../` sequence or an absolute path causes the filebeat processing container to create directories outside the intended extraction directory. Version 26.07.0 fixes the issue.
- CVE-2026-63133Medium
Malcolm is a network traffic analysis tool suite. Prior to version 26.07.0, `safe-extract.py` extracts uploaded archives with no limit on entry count, directory depth, total entries, or output size. A small malicious archive containing a large number of directory or file entries causes the filebeat processing container to create an unbounded number of filesystem objects, exhausting inodes or filesystem metadata and denying service to the processing pipeline and any service sharing the same mount. Version 26.07.0 fixes the issue.
- CVE-2026-55676High
Malcolm, a network traffic analysis tool, has a vulnerability in its file-upload component (FilePond PHP backend). The allowed file types list is empty by default, so all extensions are accepted, and filenames keep the .php extension. An authenticated user with the ROLE_UPLOAD role can upload a PHP file and execute it as www-data.
Original NVD description (English source)
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.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS