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Threats / Microsoft / CVE-2017-11826
CVE-2017-11826 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Microsoft Office vulnerability

Microsoft Office remote code execution via improper memory object handling. Attackers can execute arbitrary code in the user's context by exploiting this vulnerability.

Verdict

Today item — known-exploited.

A memory corruption vulnerability in Microsoft Office enables remote code execution when processing specially crafted files. The high EPSS score and active exploitation indicate significant risk to organizations relying on Office for document processing.

CISA KEV Yes · 2022-03-033EPSS 0.81627 (verify live)4Exploit Public PoC5
01

Is it exploitable?

— the evidence, ranked above the score
Exploit 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
4 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 2022-03-03).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.81627 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Microsoft, Office. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-119 Memory Buffer Bounds Error — weakness family: Memory safety.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
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
I craft a malicious Office document containing specially formatted objects designed to trigger memory corruption.
Business
Employees receive phishing emails with weaponized Office attachments, leading to endpoint compromise and potential lateral movement.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I deliver the malicious document via email or web download, targeting users who open it in vulnerable Office versions.
Business
User opens the file, triggering code execution with their privileges, exposing sensitive data and enabling further network infiltration.
3

Lateral reach — past segmentation narrative 3

Attacker
I execute arbitrary code within the Office process, establishing persistence or deploying secondary payloads.
Business
Attackers gain foothold for data exfiltration, credential theft, or deployment of malware across the organization.
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)
  • Public PoC available (VulnCheck)
  • 4 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • 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.