High severity · published Sep 21, 2026
CVE-2026-83621
ntopng: Missing Authorization Check in REST API Allows Non-Admin Users to Tamper Threat Intelligence Blacklist URLs
8.1
CVSS
0.5%
EPSS
No
On KEV
Description
ntopng is a web-based network traffic monitoring application. Prior to 6.7.260717, POST /lua/rest/v2/edit/system/edit_blacklist.lua in scripts/lua/rest/v2/edit/system/edit_blacklist.lua lacks an administrator check and calls lists_utils.editList for any authenticated user. The list_name, list_enabled, url, and list_update parameters allow a non-admin user to redirect threat-intelligence downloads to attacker-controlled content, disable blocklists, or prevent scheduled updates. The changes are persisted through Redis and reloaded without a lower-level authorization guard, undermining the integrity and availability of ntopng's threat-intelligence monitoring. This issue is fixed in version 6.7.260717.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 45% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NT
ntopng · ntop
< 6.7.260717 · source: vendor
Affected product
NT
ntopng
ntop
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