Skip to content

RadicalNotion.AI

We do not sell or share your personal information

© 2026 RadicalNotion.AI

Security Data

CWE Directory
CAPEC Directory
CNA Directory
CNA Report Cards
Data Sources

Calculators

CVSS Calculator
CVSS 4.0
CVSS 3.1
CVSS 3.0
CVSS 2.0

Platform

My Vulnerabilities
Insights
Notifications
Account
Pricing

Learn

All guides
What is a CVE?
What is CVSS?
The CISA KEV catalog
What is EPSS?

Company

About us
Blog
Book a demo

Get Started

Sign up
Log in

Legal

Privacy
Terms

Security data

Weaknesses (CWE)The MITRE CWE weakness catalog
Attack Patterns (CAPEC)MITRE CAPEC attack patterns
CNAsNumbering authorities + report cards
VendorsVulnerabilities by vendor

Tools

CVSS CalculatorScore CVSS 4.0, 3.1, 3.0 & 2.0

Resources

LearnPlain-English security guides
Data SourcesHow we source CVE data

About Us Blog Pricing Book a Demo

Log in

Home
Vendors
Synology
Skynas Firmware

synology skynas firmware Vulnerabilities: CVEs, CISA KEV & Security Advisories

13 CVEs

1 in CISA KEV

synology skynas firmware Vulnerabilities

CVE security advisories and vulnerability history for skynas firmware by synology.

13

Total CVEs

Published

1

In CISA KEV

Exploited in the wild

1

Public exploits

With known exploit

8.2

Avg CVSS

2019–2021

Last updated February 26, 2021

Overview

synology skynas firmware has 13 published CVE records since 2019, of which 1 are in CISA's Known Exploited Vulnerabilities catalog and 1 have a known public exploit. The average CVSS base score across scored CVEs is 8.2.

This page aggregates every publicly disclosed vulnerability (CVE) affecting synology skynas firmware, with a severity breakdown, the affected and patched versions, the most common weakness types, and the full CVE list.

Severity and exploitation

How the CVSS severity of synology skynas firmware's CVEs breaks down, plus how many are exploited in the wild or have public exploit code.

Critical4

High6

Medium2

Low0

1 additional CVE has no CVSS severity score.

In CISA’s Known Exploited Vulnerabilities catalog

1

One of synology skynas firmware's CVEs is confirmed exploited in the wild.

Public exploits

1

One of synology skynas firmware's CVEs has a known public exploit available.

Affected versions and CVEs

Browse every synology skynas firmware version named in a CVE, then pick one to see only the CVEs that affect it.

Fixed in

6.2.3-254263 CVEs

Find a version

13 CVEs

Sort

Vulnerability · 2021-02-26
CVE-2021-26567
Patch
CWE-121
Unscored
EPSS 1.1% (79th pct)2021-02-26
High vulnerability · 2021-02-26
CVE-2021-26566
Patch
CWE-201
High · CVSS 8.3
EPSS 0.5% (68th pct)2021-02-26
High vulnerability · 2021-02-26
CVE-2021-26565
Patch
CWE-319
High · CVSS 8.3
EPSS 0.3% (55th pct)2021-02-26
High vulnerability · 2021-02-26
CVE-2021-26564
Patch
CWE-319
High · CVSS 8.3
EPSS 0.1% (33th pct)2021-02-26
High vulnerability · 2021-02-26
CVE-2021-26563
Patch
CWE-863
High · CVSS 8.2
EPSS 0.1% (30th pct)2021-02-26
Critical vulnerability · 2021-02-26
CVE-2021-26562
Patch
CWE-787
Critical · CVSS 9.0
EPSS 1.4% (81th pct)2021-02-26
Critical vulnerability · 2021-02-26
CVE-2021-26561
Patch
CWE-121
Critical · CVSS 9.0
EPSS 2.3% (85th pct)2021-02-26
Critical vulnerability · 2021-02-26
CVE-2021-26560
Patch
CWE-319
Critical · CVSS 9.0
EPSS 0.2% (37th pct)2021-02-26
Critical vulnerability · 2021-01-26
CVE-2021-3156
CISA KEV
Public exploit
Patch
CWE-193
Added to CISA KEV 2022-04-06
Critical · CVSS 9.3
EPSS 92.6% (100th pct)2021-01-26
High vulnerability · 2020-10-29
CVE-2020-27652
Patch
CWE-327
High · CVSS 8.3
EPSS 0.4% (62th pct)2020-10-29
Medium vulnerability · 2020-10-29
CVE-2020-27650
Patch
CWE-614
Medium · CVSS 5.8
EPSS 0.2% (38th pct)2020-10-29
High vulnerability · 2020-10-29
CVE-2020-27648
Patch
CWE-295
High · CVSS 8.3
EPSS 0.2% (41th pct)2020-10-29
Medium vulnerability · 2019-04-09
CVE-2019-3870
Patch
CWE-276
Medium · CVSS 6.1
EPSS 0.5% (68th pct)2019-04-09

Common weakness types

The CWE weakness categories most often found in synology skynas firmware CVEs. Follow any weakness for its full explanation.

CWE-319Cleartext Transmission of Sensitive Information3 CVEs
CWE-121Stack-based Buffer Overflow2 CVEs
CWE-201Insertion of Sensitive Information Into Sent Data1 CVE
CWE-276Incorrect Default Permissions1 CVE
CWE-295Improper Certificate Validation1 CVE
CWE-193Off-by-one Error1 CVE
CWE-327Use of a Broken or Risky Cryptographic Algorithm1 CVE
CWE-614Sensitive Cookie in HTTPS Session Without 'Secure' Attribute1 CVE

Disclosure activity by year

How many synology skynas firmware CVEs were published each year.

2019

1

2020

3

2021

9

Other synology products

Browse vulnerabilities for other products by synology.

diskstation manager136 CVEs router manager63 CVEs DiskStation Manager (DSM)53 CVEs Synology Router Manager (SRM)43 CVEs photo station33 CVEs skynas29 CVEs Surveillance Station25 CVEs vs960hd22 CVEs

All synology vulnerabilities

Frequently asked questions

Common questions about synology skynas firmware vulnerabilities.

How many CVEs does synology skynas firmware have?

synology skynas firmware has 13 published CVE records since 2019.

How many synology skynas firmware CVEs are in CISA KEV?

Yes — 1 of synology skynas firmware's CVEs are listed in CISA's Known Exploited Vulnerabilities catalog, confirmed exploited in the wild and carrying a CISA remediation deadline.

Are there public exploits for synology skynas firmware vulnerabilities?

Yes — 1 of synology skynas firmware's CVEs have a known public exploit.

Which versions of synology skynas firmware are affected?

1 distinct synology skynas firmware version is named across its CVEs. Use the version filter above to see the CVEs affecting a specific version.

What are the most common weakness types in synology skynas firmware CVEs?

synology skynas firmware's CVEs most often map to these CWE weakness types: CWE-319 (Cleartext Transmission of Sensitive Information), CWE-121 (Stack-based Buffer Overflow), CWE-201 (Insertion of Sensitive Information Into Sent Data), CWE-276 (Incorrect Default Permissions).

How many critical synology skynas firmware vulnerabilities are there?

synology skynas firmware has 4 critical and 6 high-severity CVEs.

What is the average severity of synology skynas firmware CVEs?

The average CVSS base score across synology skynas firmware's scored CVEs is 8.2.

References

All synology vulnerabilities
The MITRE CVE Program (opens in a new tab)
Learn: What is a CVE?
CWE directory: the weakness types these CVEs map to

Vulnerability data is sourced from the CVE Program; severity, KEV, and exploit signals are aggregated by RadicalNotion.AI.

Track synology skynas firmware vulnerabilities

Monitor new synology skynas firmware vulnerabilities as they are disclosed, with AI-written analysis and remediation guidance.

Start free See pricing

On this page

Overview
Severity and exploitation
Affected versions and CVEs
Common weakness types
Disclosure activity
Other products
FAQ
References