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Threats / Microsoft / CVE-2017-0199
CVE-2017-0199 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Microsoft Office and WordPad vulnerability

Microsoft Office and WordPad contain a remote code execution vulnerability in file parsing. The flaw enables attackers to execute arbitrary code through specially crafted documents.

Verdict

Today item, not a backlog item.

A critical remote code execution vulnerability in Microsoft Office and WordPad file parsing. Exploitation is active in the wild and associated with ransomware campaigns, presenting immediate risk to organizations and users opening untrusted documents.

CISA KEV Yes · 2021-11-033Ransomware use Flagged3EPSS 0.99933 (verify live)4Exploit Weaponized · public PoC5
01

Is it exploitable?

— the evidence, ranked above the score
Exploit available
Fully weaponized — public exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
135 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), flagged for known ransomware use.
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.99933 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Microsoft, Office and WordPad. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
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
Craft a malicious Office or WordPad document that exploits the file parsing vulnerability.
Business
Attackers gain ability to execute code with user privileges on affected systems.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
Distribute the weaponized document via email, web, or file-sharing platforms to target users.
Business
Widespread exposure across enterprise and consumer user bases increases infection surface.
3

Lateral reach — past segmentation narrative 3

Attacker
Execute ransomware payload or establish persistent access upon successful exploitation.
Business
Systems become compromised, leading to data encryption, operational disruption, and financial extortion.
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)
  • Ransomware-use flag (CISA)
  • EPSS probability (FIRST)
  • Weaponized exploit available (VulnCheck)
  • 135 reported-exploitation source(s)
  • Public exploit availability
  • 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.