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TI-2026-69637 Aliases CVE-2026-107334GHSA-rgrh-q687-4gc8

Incorrect authorization in Malcolm exposes role-restricted paths

Priority MEDIUM 58CWE-863Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
Low · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-863.

Summary

Malcolm from 0 through 26.07.1 is affected. Its nginx Lua role-based access control layer checks the raw percent-encoded request URI, while nginx selects the serving location from the decoded URI, so the check can be skipped (CWE-863). An authenticated user with low privileges can reach admin-only paths that the access control is meant to restrict.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

Description from the CNA

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00213 11th percentileScored 2026-11-07
Fix Fixed Malcolm (CISA): 26.08.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
CISAMalcolmup to 26.07.126.08.0Patch availableCNA
  • Malcolm VendorCISA Affected up to 26.07.1 Fixed in 26.08.0 Patch available CNA

Remediation

Upgrade Malcolm to 26.08.0, the fixed version.

Written with Claude Haiku 5.5 from the sources below · 2026-10-29

  • Fix · CNA Malcolm (CISA) Fixed in 26.08.0

Timeline

  1. 2026-10-08 Threatist record created from CVE-2026-107334
  2. 2026-10-09 Alias added: GHSA-rgrh-q687-4gc8
  3. 2026-10-09 CISA SSVC decision points changed

References

Other 2

  • TI-2026-69642 Server-side request forgery in Malcolm file upload component CVSS 3.1HIGH 7.1
  • TI-2026-69640 Cross-Site Request Forgery in Malcolm CVSS 3.1HIGH 7.1
  • TI-2026-69638 Compressed file uploads in Malcolm can exhaust shared disk space CVSS 3.1MEDIUM 6.5
  • TI-2025-24590 CISA Thorium download stream divide by zero CVSS 4.0MEDIUM 5.3
  • TI-2025-24585 CISA Thorium insecure downloaded file path validation CVSS 4.0MEDIUM 5.3
  • TI-2025-41377 Software Acquisition Guide Supplier Response Web Tool XSS CVSS 4.0MEDIUM 4.6
See all 33 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences