Synology Note Station up to 2.5.1 Attachment Preview cross site scripting

CVSS Meta Temp Score
CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.
Current Exploit Price (≈)
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CTI Interest Score
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A vulnerability was found in Synology Note Station up to 2.5.1. It has been declared as problematic. Affected by this vulnerability is an unknown function of the component Attachment Preview. The manipulation with an unknown input leads to a cross site scripting vulnerability. The CWE definition for the vulnerability is CWE-79. The software does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. As an impact it is known to affect integrity. The summary by CVE is:

Cross-site scripting (XSS) vulnerability in Attachment Preview in Synology Note Station before 2.5.1-0844 allows remote authenticated users to inject arbitrary web script or HTML via malicious attachments.

The bug was discovered 01/23/2018. The weakness was published 05/09/2018 (Website). The advisory is shared at This vulnerability is known as CVE-2018-8911 since 03/22/2018. The attack can be launched remotely. The successful exploitation requires a single authentication. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

The vulnerability was handled as a non-public zero-day exploit for at least 106 days. During that time the estimated underground price was around $0-$5k.

Upgrading to version 2.5.1-0844 eliminates this vulnerability.

Similar entry is available at 117566.





  • commercial

CPE 2.3info

CPE 2.2info


VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.4
NVD Vector: 🔍

CNA Base Score: 6.5
CNA Vector (Synology Inc.): 🔍



VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍


Class: Cross site scripting
CWE: CWE-79 / CWE-74 / CWE-707
ATT&CK: T1059.007

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍


Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍


Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: Note Station 2.5.1-0844


01/23/2018 🔍
03/22/2018 +58 days 🔍
05/09/2018 +47 days 🔍
05/09/2018 +0 days 🔍
05/10/2018 +1 days 🔍
03/11/2023 +1766 days 🔍



Advisory: SA_18_03
Status: Not defined
Confirmation: 🔍

CVE: CVE-2018-8911 (🔍)
See also: 🔍


Created: 05/10/2018 10:04 AM
Updated: 03/11/2023 02:09 PM
Changes: 05/10/2018 10:04 AM (58), 02/04/2020 08:35 AM (3), 03/11/2023 02:08 PM (4), 03/11/2023 02:09 PM (12)
Complete: 🔍


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