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Threats / Microsoft / CVE-2021-38645
CVE-2021-38645 · EUVD no mirror located · GCVE no mirror located Verified 2026-08-04

Microsoft Open Management Infrastructure (OMI) vulnerability

Microsoft Open Management Infrastructure (OMI) contains an unspecified privilege escalation vulnerability affecting Azure VM Management Extensions. The flaw has been exploited in the wild.

Verdict

Today item — known-exploited.

An unauthenticated or low-privileged attacker can escalate privileges on affected Azure virtual machines through OMI, potentially gaining administrative control of the system and any workloads it hosts.

CISA KEV Yes · 2021-11-035EPSS 0.0189 (verify live)6CVSS 7.83CISA SSVC Exploitation: active · Automatable: no · Impact: total4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
3 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).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.0189 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
CVSS 7.8 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C) · Affected: Microsoft, Open Management Infrastructure (OMI). Confirm exact fixed builds in the vendor advisory.CVSS — CNA-assigned (CVE.org), version 3.1, set at disclosure.
CVE.org ↗Reported
CISA SSVC (triage disposition)
Exploitation: active · Automatable: no · 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.
CISA-ADP ↗Reported
Currency of the record
CISA added this to its KEV catalog 49 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 urgency
Attribution 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 board
1

Front door — unauthenticated access narrative 1

Attacker
I identify an Azure VM running OMI with the vulnerable version exposed through management interfaces.
Business
Attackers gain a foothold into cloud infrastructure with potential access to sensitive data and compute resources.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I exploit the privilege escalation flaw to elevate from limited to administrative access on the target VM.
Business
Compromised VMs can be used to pivot laterally across the Azure environment or exfiltrate confidential information.
3

Lateral reach — past segmentation narrative 3

Attacker
I maintain persistence and control over the compromised infrastructure for ongoing operations.
Business
Extended dwell time increases exposure window and enables attackers to establish backdoors or deploy additional malware.
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

Coverage & confidence

— what we know, and what we don’t

Established (cited)

  • KEV listing (CISA)
  • EPSS probability (FIRST)
  • 3 reported-exploitation source(s)
  • CVSS 7.8 — CNA-assigned (CVE.org)
  • CISA SSVC triage disposition (CVE.org ADP)
  • Catalogued by microsoft (CNA)
  • Coverage gaps — stated, not hidden

  • No EUVD / GCVE mirror in feed — single-authority dependency for the identifier.
  • EPSS & exposure are time-varying; verify live at the source.
  • Threat-actor attribution not established from feed data — absence of a name is not absence of compromise.
  • No finder/reporter credit recorded in the public CVE entry — the work behind this find is unattributed.
  • Disclosure & credit2
    Catalogued by microsoftCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.