---
id: "CVE-2026-81559"
page: "https://infrastack.ai/live/CVE-2026-81559"
kind: "vulnerability"
aliases: ["CVE-2026-81559"]
title: "Synology DSM: TaskScheduler API lets authenticated users write files"
severity: "medium"
cvss: 4.3
epss: null
exploited: false
status: "open"
category: "infrastructure"
products: []
ecosystems: []
tags: ["dsm", "infrastructure", "nas", "self-hosted", "synology"]
not_affected_if: ["fixed-version", "no-remote-accounts"]
published_at: "2026-11-12T04:17:21+00:00"
first_seen_at: "2026-11-12T04:47:10+00:00"
updated_at: "2026-11-12T04:48:02+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-81559", "first_seen_at": "2026-11-12T04:47:10+00:00"}]
exploit_sources: []
---

# Synology DSM: TaskScheduler API lets authenticated users write files

Link for people: https://infrastack.ai/live/CVE-2026-81559 (this .md is for agents)

Synology DiskStation Manager has a missing authorization check in its TaskScheduler API. A remote user with a valid account can write specific files on the NAS.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed DSM version in Control Panel > Info Center (or run `cat /etc/VERSION` over SSH) and compare it with the fixed releases.

## Fix

- Move DSM to `7.3.2-86009-5` or later on the 7.3 branch, or `7.4.1-90080-1` or later on the 7.4 branch.

## Timeline

- 2026-11-12T04:47:10+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-81559

## From the sources

A missing authorization vulnerability in the TaskScheduler API in Synology DiskStation Manager (DSM) before 7.3.2-86009-5 and 7.4.1-90080-1 allows remote authenticated users to write specific files.

---

_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_