# CVE-2026-83621: ntopng: Missing Authorization Check in REST API Allows Non-Admin Users to Tamper Threat Intelligence Blacklist URLs

> Non-admin users can modify threat intelligence blacklists in ntopng due to missing authorization checks, compromising monitoring integrity.

- **Severity:** High 8.1 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 21 Sep 2026
- **Updated:** 21 Sep 2026
- **Also known as:** AZL-103404, GHSA-ffg5-889g-f5q8, UBUNTU-CVE-2026-83621

## What is CVE-2026-83621?

CVE-2026-83621 is a high-severity missing authorization vulnerability in ntopng, published on 21 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official 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.

Weakness: CWE-862 (Missing Authorization)

## Which versions are affected by CVE-2026-83621?


## How do I fix CVE-2026-83621?

No fix has been published for CVE-2026-83621 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-83621 being exploited?

There is no known exploitation of CVE-2026-83621 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-83621 and fix it if it is affected.

What it is: CVE-2026-83621 is a high-severity missing authorization vulnerability in ntopng, published on 21 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-83621 in the wild and no public exploit code.

Affected product: ntopng. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-83621/ (Markdown: https://insights.sbomify.com/CVE-2026-83621/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-83621
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-83621
- OSV: https://osv.dev/vulnerability/CVE-2026-83621

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-83621/
Summaries are generated and may contain mistakes; the official description above is the record.