CVE-2020-1350
CriticalExploitedPublic exploitA remote code execution vulnerability exists in Windows Domain Name System servers when they fail to properly handle requests, aka 'Windows DNS Server Remote Code Execution Vulnerability'.
Published Jul 14, 2020 · Updated Dec 17, 2025 · Also known as SIG Red, SIGRed
Key Facts
Patch immediately- CVE-2020-1350 is a critical-severity vulnerability (CVSS 10.0 v3.1) affecting Windows Server 2008 (Microsoft), Windows Server 2012 (Microsoft), Windows Server 2016 (Microsoft) and 5 more products.
- It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Oct 20, 2020. Public exploit code is available.
- EPSS estimates a 97% probability of exploitation in the next 30 days.
- No fixed version is listed yet; check the vendor advisory for mitigations.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
10.0
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
97%
Higher than 99.8% of all scored CVEs
Exploited in the wild
Yes
4 catalog listings
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2020-1350 brief as a PDF
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Description
A remote code execution vulnerability exists in Windows Domain Name System servers when they fail to properly handle requests, aka 'Windows DNS Server Remote Code Execution Vulnerability'.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| CISA KEV | Nov 3, 2021 | May 3, 2022 | Not reported |
| Industry KEV feed | Oct 20, 2020 | May 3, 2022 | Not reported |
| CIRCL KEV | Nov 3, 2021 | May 3, 2022 | Not reported |
| ENISA EUVD | Nov 3, 2021 | n/a | Not reported |
Required action: Apply updates per vendor instructions.
Affected Products
10 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Windows Server 2008Microsoft | r2-sp1 | n/a |
| Windows Server 2012Microsoft | r2 | n/a |
| Windows Server 2016Microsoft | See advisory | n/a |
| Windows Server 2019Microsoft | See advisory | n/a |
| Windows Server | >= 2019 | n/a |
Timeline
Publicly disclosed
Jul 14, 2020
Added to Industry KEV feed
Oct 20, 2020
Added to CISA KEV
Nov 3, 2021
Added to CIRCL KEV
Nov 3, 2021
Added to ENISA EUVD
Nov 3, 2021
Last updated
Dec 17, 2025
Weakness Type
- CWE-20 Improper Input Validation
References
- advisoryhttp://packetstormsecurity.com/files/158484/SIGRed-Windows-DNS-Denial-Of-Service.html
- patchhttps://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1350
- exploitVulnCheck exploitation report
- exploitVulnCheck exploitation report
- exploitVulnCheck exploitation report
FAQ
Common Questions.
A remote code execution vulnerability exists in Windows Domain Name System servers when they fail to properly handle requests, aka 'Windows DNS Server Remote Code Execution Vulnerability'.
Affected: Windows Server 2008 (Microsoft) versions r2-sp1; Windows Server 2012 (Microsoft) versions r2; Windows Server 2016 (Microsoft), among others. The full list is in the CVE brief.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Oct 20, 2020.
Yes. It was added on Nov 3, 2021 with a federal remediation due date of May 3, 2022.
Public exploit code is available.
No fixed version is listed yet; check the vendor advisory for mitigations.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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