Security Resilience

CVE-2020-1350

Microsoft Windows Server 2008 r2

CISA KEVActive ExploitationEUVD ExploitedPublic PoC
Published
14 July 2020
Modified
18 December 2025
KEV Added
03 November 2021
Patch / advisory
CVSS Score v3.1 10.0
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS Score 0.97 99.9th percentile
Risk Priority 100 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2020-1350 is a critical-severity Improper Input Validation (CWE-20) vulnerability in Microsoft Windows Server 2008. Its CVSS base score is 10.0 (Critical).

Operationally, ranked in the top 0.1% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

A remote code execution vulnerability exists in Windows Domain Name System servers when they fail to properly handle requests. The flaw, tracked as CVE-2020-1350 and also known as SIGRed, affects the DNS server component in supported Windows versions and carries a maximum CVSS score of 10.0 due to its network-accessible nature and full system impact.

An unauthenticated attacker can exploit the issue remotely by sending specially crafted DNS requests, achieving arbitrary code execution with the privileges of the DNS service. Successful exploitation grants complete control over confidentiality, integrity, and availability on the target server and can extend impact to other systems because of the changed scope.

Microsoft's security advisory and the CISA Known Exploited Vulnerabilities catalog both address the issue, directing administrators to apply the vendor-supplied patches. Public proof-of-concept material has also appeared demonstrating denial-of-service outcomes that align with the same root cause.

The vulnerability appears in the CISA catalog of actively exploited flaws, confirming real-world use against unpatched Windows DNS deployments.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

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'.

CWE(s)
KEV Date Added
03 November 2021

Related Threats

Threat-Actor AttributionAI

Microsoft Corp. (Salesforce / Slack engineer recruitment claims)
Potential for China Cyber Response to Heightened U.S.–China Tensions | CISA
APT1 (G0006)
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Deep Panda (G0009)
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APT3 (G0022)
Potential for China Cyber Response to Heightened U.S.–China Tensions | CISA
Winnti Group (G0044)
Potential for China Cyber Response to Heightened U.S.–China Tensions | CISA
menuPass (G0045)
Potential for China Cyber Response to Heightened U.S.–China Tensions | CISA
Leviathan (G0065)
Potential for China Cyber Response to Heightened U.S.–China Tensions | CISA
APT19 (G0073)
Potential for China Cyber Response to Heightened U.S.–China Tensions | CISA
APT41 (G0096)
Potential for China Cyber Response to Heightened U.S.–China Tensions | CISA
AnonOps
Potential for China Cyber Response to Heightened U.S.–China Tensions | CISA

CVEs Like This One

CVE-2020-1040Same product: Microsoft Windows Server 2008both on KEV
CVE-2023-36563Same product: Microsoft Windows Server 2008both on KEV
CVE-2023-36706Same product: Microsoft Windows Server 2008
CVE-2025-32706Same product: Microsoft Windows Server 2008both on KEV
CVE-2021-36942Same product: Microsoft Windows Server 2008both on KEV
CVE-2025-29968Same product: Microsoft Windows Server 2008
CVE-2024-43455Same product: Microsoft Windows Server 2008
CVE-2024-30040Same product: Microsoft Windows Server 2016both on KEV
CVE-2012-0151Same product: Microsoft Windows Server 2008both on KEV
CVE-2023-36707Same product: Microsoft Windows Server 2012

Affected Assets

microsoft
windows server 2008
all versions, r2
microsoft
windows server 2012
all versions, r2
microsoft
windows server 2016
all versions
microsoft
windows server 2019
all versions

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-20

Security testing and developer training directly verify and enforce proper input validation, reducing exploitability of injection and malformed-data weaknesses.

addresses: CWE-20

Security testing and evaluation at multiple SDLC stages directly detects missing or flawed input validation, with the required remediation process ensuring fixes are applied.

addresses: CWE-20

Directly implements checks on information inputs to reject invalid data before processing.

addresses: CWE-20

Spam protection mechanisms perform filtering and detection on inbound/outbound messages, directly compensating for missing or weak input validation of unsolicited content.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

blocks

A.8.25 mandates security requirements, secure coding guidelines, checkpoints, testing (incl. code scans) and developer training in the SDLC, which reaches a slice of input validation defects but leaves the majority (incomplete enforcement, second-order inputs, parser differentials, post-validation canonicalization) unaddressed as in the SA-3 and A.8.28 anchors.

blocks

Mandating input controls that include integrity checks and input validation ensures that untrusted data is examined before use, blocking the root cause of many injection and malformed-data weaknesses.

blocks

Security-by-design principles explicitly call for data validation and sanitization at every layer, reducing the chance that malformed or malicious input will be processed without scrutiny.

prevents

Requiring language-specific secure coding standards, peer review, SAST and documented mitigation of common programming errors forces validation of all inputs before they are trusted.

finds

Testing against a defined set of requirements and using code review plus vulnerability scanning forces validation of inputs and handling of unanticipated conditions, reducing the chance that malformed data will be accepted.

Hardening callouts derived

DISA STIG baselines are authored against specific weaknesses. Where this CVE cites a broad weakness class, the mapping is not asserted at that abstraction (owner ruling, 2026-09-25: grade only at Base and below), so no rule is shown here rather than a rule shown against the wrong grain.

  • No fine-grained STIG row for CWE-20, a class-level weakness, and none of its children carries one either.

References