Security Digest · Vulnerability record
CVE-2026-13684: Synology DiskStation Manager (DSM) vulnerability
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.
CVSS 9.8 Critical EPSS 0.6% · p49 Act now
Should you act?
Critical and remotely reachable
No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.
- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.6%, percentile 49: FIRST’s model estimates a 0.6% chance of exploitation activity in the next 30 days, higher than 49% of all scored CVEs (low). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Editorial verdict: Act now. Synology DSM: C3RB3R Ransomware Hits Unpatched NAS — Ransomware operators are encrypting Synology NAS boxes through DSM flaws that were patched in September 2026 and late 2024; if your DSM is behind the SA-26:13 builds, update today and get its admin interface off the internet.
What it is
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.
Weakness type: CWE-116.
Product: Synology DiskStation Manager (DSM) · Assigned by: synology · Published: 2026-09-18
Affected and fixed versions
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| Synology | DiskStation Manager (DSM) | 7.4 < 7.4-90075, 7.3.2 < 7.3.2-86009-4, 7.2.2 < 7.2.2-72806-9, 7.2.1 < 7.2.1-69057-12 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| synology | 3.1 | 9.8 Critical | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- Attack vector: network (remotely reachable)
- Attack complexity: low
- Privileges required: none (no login)
- User interaction: none
- Scope: unchanged
CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.
Exploitation and urgency
- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none, automatable yes, technical impact total.
- FIRST EPSS (model of 2026-11-04): 0.60% probability of exploitation activity in the next 30 days; percentile 49.
Timeline
- — CVE record last updated
- — CVE record published by synology
- — erroneo.us brief: Synology DSM: C3RB3R Ransomware Hits Unpatched NAS
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vulnerability records
- CVE.org record CVE-2026-13684 cve.org
- NVD entry CVE-2026-13684 nvd.nist.gov
Other references from the CVE record and advisory
- Synology-SA-26:13 DSM synology.com