# CVE-2025-11837 — QNAP Systems Inc. Malware Remover

> As of 2026-01-05, CVE-2025-11837 is a CRITICAL-severity vulnerability in QNAP Systems Inc. Malware Remover, CVSS v3.1 9.8, EPSS 0.7% (50.9th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2025-11837, most recently “AryStinger (Ary-Attack) Botnet Compromises 4,000+ Legacy D-Link/RTL819X Routers and NAS for Global Attack Proxy Infrastructure (CVE-2013-3307, CVE-2016-5681, CVE-2025-11837)”.

**Last updated:** 2026-01-05

## What is CVE-2025-11837?

An improper control of generation of code vulnerability has been reported to affect Malware Remover. The remote attackers can then exploit the vulnerability to bypass protection mechanism. We have already fixed the vulnerability in the following version: Malware Remover 6.6.8.20251023 and later

The record classifies CVE-2025-11837 under weakness class [CWE-94](https://cwe.mitre.org/data/definitions/94.html). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on confidentiality, integrity, availability. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 254 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 9.8 — CRITICAL (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **CVSS v4.0 base score:** 8.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U`)
- **EPSS (FIRST):** 0.7% probability of exploitation in the next 30 days, higher than 50.9% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 6.9/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-01-02, last modified 2026-01-05

## Is CVE-2025-11837 being exploited?

No public exploitation evidence for CVE-2025-11837 is recorded in the sources Threadlinqs tracks — CISA KEV, Exploit-DB, public proof-of-concept repositories and ProjectDiscovery Nuclei — as of 2026-01-05. That is an absence of evidence in those feeds, not a guarantee that the vulnerability is unexploited.

## Affected products and versions

- **QNAP Systems Inc.**: Malware Remover

## How to fix CVE-2025-11837

Vendor advisory: [https://www.qnap.com/en/security-advisory/qsa-25-47](https://www.qnap.com/en/security-advisory/qsa-25-47). Apply the vendor fix referenced above to every affected product listed in this record, then confirm the running version against the vendor advisory.

## Threat activity tracking CVE-2025-11837

1 tracked threat in the Threadlinqs corpus references CVE-2025-11837, either in the campaign’s CVE list or as an indicator on the campaign record.

- [AryStinger (Ary-Attack) Botnet Compromises 4,000+ Legacy D-Link/RTL819X Routers and NAS for Global Attack Proxy Infrastructure (CVE-2013-3307, CVE-2016-5681, CVE-2025-11837)](https://intel.threadlinqs.com/threat/TL-2026-0894) — HIGH · 2026-06-21

## Sources

Enriched from CVE.org, NVD, FIRST EPSS, GitHub Security Advisories. Last verified by Threadlinqs on 2026-06-22. This product uses the NVD API but is not endorsed or certified by the NVD.

**Other references**

- [qnap.com](https://www.qnap.com/en/security-advisory/qsa-25-47)

Canonical: https://intel.threadlinqs.com/cve/CVE-2025-11837
Full detection coverage and IOCs for threats exploiting CVE-2025-11837 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp