CVE Intelligence
High

CVE-2017-8509 — A remote code execution vulnerability exists in Microsoft Office when the software fails to...

A remote code execution vulnerability exists in Microsoft Office when the software fails to properly handle objects in memory, aka "Office Remote Code Execution Vulnerability". This CVE ID is unique from CVE-2017-8510, CVE-2017-8511, CVE-2017-8512, CVE-2017-0260, and CVE-2017-8506.

Published Jun 14, 2017 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: microsoft

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 18.2% (30-day exploitation probability)+15
  • Technical severity (high)+6

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
18.24%
ahead of 97% of scored CVEs · Oct 15, 2026
Affects
Microsoft
Office and 7 more
CVSS base
8.8
High · 2 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
None
none · proof-of-concept · active
Automatable
No
can an attacker script the kill-chain steps
Technical impact
Total
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Microsoft Office, Microsoft Office Compatibility Pack, Microsoft Office Web Apps…).
  2. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  3. Apply the fixed version or the patch documented under Remediation.
  4. Exploitation requires user interaction: tighten email/web filtering and warn affected users.
  5. EPSS ahead of 97% of scored CVEs: prioritize it in the patch queue.
  6. Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Microsoft Office version 2007-sp3version 2010-sp2version 2013-sp1version 2016 Vulnerable NIST National Vulnerability Database
Microsoft Office version Microsoft Office 2007 Service Pack 3, Microsoft Office Compatibility Pack Servic Vulnerable CVE Program (cve.org) e CISA ADP
Microsoft Office Compatibility Pack versions not specified by the source Vulnerable NIST National Vulnerability Database
Microsoft Office Web Apps version 2010 Vulnerable NIST National Vulnerability Database
Microsoft Office Web Apps Server version 2013 Vulnerable NIST National Vulnerability Database
Microsoft Onenote version 2010 Vulnerable NIST National Vulnerability Database
Microsoft Sharepoint Server version 2013-sp1version 2016version 2010-sp2 Vulnerable NIST National Vulnerability Database
Microsoft Word version 2007-sp3version 2010-sp2version 2013-sp1version 2016 Vulnerable NIST National Vulnerability Database
Microsoft Word For Mac version 2016 Vulnerable NIST National Vulnerability Database

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
8.8 CVSS 3.0 High 2.8 5.9 nvd@nist.gov via NIST National Vulnerability Database
8.8 CVSS 3.0 High — — GitHub, Inc. via GitHub Security Advisories
9.3 CVSS 2.0 High 8.6 10.0 nvd@nist.gov via NIST National Vulnerability Database
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H (score shown at the top: nvd@nist.gov)

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · microsoft corporation/microsoft office
    Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 15, 2026
  • Fix documented
    Oct 15, 2026 · NIST National Vulnerability Database
  • Affected products added · microsoft/office, microsoft/office compatibility pack, microsoft/office web apps, microsoft/office web apps server, micr
    Oct 15, 2026 · NIST National Vulnerability Database
  • CVSS changed · 8.8
    Oct 15, 2026 · NIST National Vulnerability Database
  • Source status changed · → Modified
    Oct 15, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 15, 2026 · Alertas do Telegram
  • 2017
  • CVE published
    Jun 14, 2017 · microsoft

Source activity

Repeated readings are counted rather than listed.

  • 2× References added · Oct 15, 2026 – Oct 15, 2026
  • 1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

4 on the record

Elsewhere on this site

Microsoft
every CVE for this vendor

Related CVEs (same products)

  • CVE-2026-97782 Microsoft Office SharePoint Tampering Vulnerability 2d
  • CVE-2026-97783 Microsoft Office SharePoint Spoofing Vulnerability 2d
  • CVE-2026-97755 Microsoft Office Excel Remote Code Execution Vulnerability 2d
  • CVE-2026-96044 Microsoft Office SharePoint Elevation of Privilege Vulnerability 2d
  • CVE-2026-88206 Microsoft Office SharePoint Elevation of Privilege Vulnerability 2d
  • CVE-2026-88209 Microsoft Office SharePoint Spoofing Vulnerability 2d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No CWE classification.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2017-8509 is "A remote code execution vulnerability exists in Microsoft Office when the software fails to...", rated High. It affects Office (Microsoft); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 8.8 describes technical severity. EPSS 18.24% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

Comments

Moderated technical discussion. Read the community guidelines.

No comments yet.

Sign in or create an account to comment and suggest corrections.