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TI-2026-15969 Aliases CVE-2026-19670GHSA-4887-2gc3-6j9r

Incorrect Authorization in CISA Malcolm

Priority MEDIUM 57CWE-863Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Security bypass
Confidentiality · integrity · availability
Low · Low · None
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-863.

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.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00239 15th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

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
cisagovMalcolmup to 26.07.1—No fix listedCNA
  • Malcolm Vendorcisagov Affected up to 26.07.1 Fixed in — No fix listed CNA

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-19670
  2. 2026-10-03 Alias added: GHSA-4887-2gc3-6j9r

References

Other 2

  • TI-2026-45069 Malcolm has Uncontrolled Resource Consumption in Archive Extraction (Inode-Exhaustion DoS) CVSS 4.0HIGH 7.1
  • TI-2026-15970 Improper handling of highly compressed data (data amplification) in CISA Malcolm CVSS 4.0HIGH 7.1
  • TI-2026-45070 Malcolm's Path Traversal in Archive Extraction Allows Arbitrary Directory Creation CVSS 4.0MEDIUM 5.3
  • TI-2026-40197 Malcolm vulnerable to RCE via unrestricted .php upload to the file-upload component CVSS 4.0HIGH 8.7
  • TI-2026-45083 Malcolm Vulnerable to Authorization Bypass via URI Normalization Differential in Nginx Lua RBAC CVSS 4.0HIGH 7.1

Sources

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