basicsecurity.net
Proof, not just disclosure.
Threats / Microsoft / CVE-2012-0158
CVE-2012-0158 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Microsoft MSCOMCTL.OCX vulnerability

Microsoft MSCOMCTL.OCX contains a code injection vulnerability enabling remote code execution with user-level privileges. The flaw has been actively exploited in the wild.

Verdict

Today item — known-exploited.

An attacker can execute arbitrary code on vulnerable systems by exploiting unsafe code evaluation in MSCOMCTL.OCX. Active exploitation in the wild combined with high EPSS score indicates immediate risk to unpatched deployments.

CISA KEV Yes · 2021-11-033EPSS 0.9999 (verify live)4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
85 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 0.9999 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Microsoft, MSCOMCTL.OCX. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-94 Code Injection — weakness family: Injection.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-94 · Code InjectionInjection
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 craft a malicious document or web content that triggers unsafe code evaluation in MSCOMCTL.OCX when processed by a target user.
Business
Employees opening untrusted files or visiting compromised websites become vectors for system compromise and data theft.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I execute arbitrary code within the security context of the user who opened the malicious content, gaining their system access level.
Business
Attackers obtain credentials, intellectual property, and lateral movement capabilities within corporate networks.
3

Lateral reach — past segmentation narrative 3

Attacker
I establish persistence and exfiltrate sensitive data or deploy additional malware payloads across the compromised environment.
Business
Organizations face data breaches, operational disruption, and potential regulatory penalties from widespread system compromise.
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)
  • 85 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • 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.