# CVE-2026-13684 — Synology DiskStation Manager (DSM)

> As of 2026-09-18, CVE-2026-13684 is a CRITICAL-severity vulnerability in Synology DiskStation Manager (DSM), CVSS v3.1 9.8, EPSS 0.5% (48.7th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2026-13684, most recently “C3RB3R (Cerber-variant) Ransomware Campaign Against Internet-Exposed Synology NAS Devices (Unpatched / End-of-Life DSM; Disputed Entry Vector: CVE-2024-10441 vs CVE-2026-13639 / CVE-2026-13684)”.

**Last updated:** 2026-09-18

## What is CVE-2026-13684?

An improper encoding or escaping of output vulnerability in SCGI in Synology DiskStation Manager (DSM) before 7.2.1-69057-12, 7.2.2-72806-9, 7.3.2-86009-4 and 7.4-90075 allows remote attackers to read or write arbitrary files and conduct denial-of-service attacks.

The record classifies CVE-2026-13684 under weakness class [CWE-116](https://intel.threadlinqs.com/cwe/CWE-116). 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 47 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`)
- **EPSS (FIRST):** 0.5% probability of exploitation in the next 30 days, higher than 48.7% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 8.8/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-09-18

## Is CVE-2026-13684 being exploited?

Weaponised exploit code for CVE-2026-13684 is publicly available. 1 public proof-of-concept repository is tracked for this identifier. It currently carries a trending score of 44 in the Threadlinqs vulnerability feed.

- [SHIFox8/synology-dsm-vuln-scanner](https://github.com/SHIFox8/synology-dsm-vuln-scanner) (github)

## Affected products and versions

- **Synology**: DiskStation Manager (DSM)

## How to fix CVE-2026-13684

No vendor patch reference has been recorded for CVE-2026-13684 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-13684

1 tracked threat in the Threadlinqs corpus references CVE-2026-13684, either in the campaign’s CVE list or as an indicator on the campaign record.

- [C3RB3R (Cerber-variant) Ransomware Campaign Against Internet-Exposed Synology NAS Devices (Unpatched / End-of-Life DSM; Disputed Entry Vector: CVE-2024-10441 vs CVE-2026-13639 / CVE-2026-13684)](https://intel.threadlinqs.com/threat/TL-2026-5044) — HIGH · 2026-11-02

## Sources

Enriched from CVE.org, NVD, FIRST EPSS, GitHub Security Advisories, public proof-of-concept repositories. Last verified by Threadlinqs on 2026-11-03. This product uses the NVD API but is not endorsed or certified by the NVD.

**Other references**

- [synology.com](https://www.synology.com/en-global/security/advisory/Synology_SA_26_13)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-13684
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