Threats / Microsoft / CVE-2020-1350
CVE-2020-1350
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-08-04
Microsoft Windows vulnerability
Microsoft Windows DNS servers fail to properly handle requests, allowing remote code execution in the Local System Account context. Known as SIGRed, this vulnerability is actively exploited in the wild.
Verdict
Today item — known-exploited.
A critical remote code execution vulnerability in Windows DNS servers with high real-world exploitation activity. The ability to execute code as Local System on DNS infrastructure poses severe risk to network availability and security.
CISA KEV Yes · 2021-11-034EPSS 0.91353 (verify live)5Exploit Public PoC6CVSS 10 (CISA)3CISA SSVC Exploitation: active · Automatable: yes · Impact: total3
01
Is it exploitable?
— the evidence, ranked above the scoreExploit available
Public proof-of-concept exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
7 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2021-11-03).
Probability (EPSS)
EPSS 0.91353 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
CVSS 10 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H) · Affected: Microsoft, Windows. Confirm exact fixed builds in the vendor advisory.CVSS — CISA-assigned via the ADP container (CVE.org), version 3.1; the CNA left no metrics, so CISA's own score is used ahead of NVD.
CISA SSVC (triage disposition)
Exploitation: active · Automatable: yes · Technical Impact: totalCISA's own stakeholder-specific triage inputs, published in the CVE record (CISA Coordinator role). NOTE: this is CISA's three decision points; the final Act/Attend/Track decision also requires a Mission & Well-being input not published here, so no overall decision is asserted.
Currency of the record
CISA added this to its KEV catalog 477 days after the CVE record was published.KEV lag = CISA-KEV dateAdded − CVE.org datePublished; a floor on how long the known-exploited flaw sat in the public record before the federal catalog listed it. Severity/weakness here is CNA- or CISA-assigned (current at disclosure), independent of NVD's analysis backlog.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution not established
No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.
03
Why it matters
— the attack path, told twice: adversary, then board1
Front door — unauthenticated access narrative 1
Attacker
I craft a malicious DNS request that exploits improper request handling in Windows DNS servers to trigger code execution.
Business
Attackers gain system-level code execution on DNS infrastructure, enabling lateral movement, data exfiltration, and network compromise.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I execute arbitrary code with Local System privileges on compromised DNS servers to establish persistence and expand access.
Business
DNS infrastructure becomes a pivot point for enterprise-wide compromise, affecting all systems relying on DNS resolution.
04
What to do
— defensible action- Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05