Microsoft Office 2010, SharePoint Enterprise Server 2010, SharePoint Server 2010, Web Applications, Office Web Apps Server 2010 and 2013, W…

published 2017-10-13 9y ago modified 2026-06-17 4mo ago also EUVD-2017-3426

cvss: 7.8; version 3.1, CNA
cisa kev: Exploited; added 2022-03-03
epss: 82.2%; EPSS 82.2% chance of exploitation in 30 days, percentile 99.6%
public exploits: 0; none known

Microsoft Office 2010, SharePoint Enterprise Server 2010, SharePoint Server 2010, Web Applications, Office Web Apps Server 2010 and 2013, Word Viewer, Word 2007, 2010, 2013 and 2016, Word Automation Services, and Office Online Server allow remote code execution when the software fails to properly handle objects in memory.

Patch / fix

cisa required action Apply updates per vendor instructions.

links 1

portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2017-11826 advisory

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Timeline

2017-09-28 Found exploited as a 0-day (Project Zero)
2017-10-10 0-day patched (Project Zero)
2017-10-13 Published
2022-03-03 Added to CISA KEV
2022-03-24 CISA patch deadline
2025-02-10 CISA SSVC: exploitation active

Known exploited

Added: 4y ago (2022-03-03)
Patch by: 2022-03-24 (4y ago)
Ransomware: Not known
Required action: Apply updates per vendor instructions.
Vendor, product: Microsoft, Office
CISA name: Microsoft Office Remote Code Execution Vulnerability

Zero-day

Detected in real attacks while still unknown to the vendor and the public, per Google Project Zero's 0day In-the-Wild tracker.

Found: 2017-09-28
Patched: 2017-10-10
Details: project zero tracker

CISA SSVC

Exploitation: Active, exploited in the wild
Automatable: no
Technical impact: total
Assessed: last yr. (2025-02-10)

Exploit prediction

82.22% chance of exploitation in the next 30 days, higher than 99.6% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

0patch.blogspot.com https://0patch.blogspot.com/2017/11/0patching-pretty-nasty-microsoft-word.html referenced PoC, tagged "exploit" by a source, unverified
tarlogic.com https://www.tarlogic.com/en/blog/exploiting-word-cve-2017-11826/ referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CISA ADP	3.1	7.8	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD	3.1	7.8	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CNA	3.1	7.8	CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
NVD	2.0	9.3	AV:N/AC:M/Au:N/C:C/I:C/A:C

Affected products

Microsoft Corporation Microsoft Office

Classification

Weakness

CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer

References

portal.msrc.microsoft.com /en-US/security-guidance/advisory/CVE-2017-11826
patch, vendor-advisory
0patch.blogspot.com /2017/11/0patching-pretty-nasty-microsoft-word.html
exploit
tarlogic.com /en/blog/exploiting-word-cve-2017-11826/
exploit, third-party-advisory
securityfocus.com /bid/101219
vdb-entry, broken-link, third-party-advisory
securitytracker.com /id/1039541
vdb-entry, broken-link, third-party-advisory
securingtomorrow.mcafee.com /mcafee-labs/analyzing-microsoft-office-zero-day-exploit-cve-2017-11826-memory-corruption-vulnerability/
broken-link, technical-description, third-party-advisory
cisa.gov /known-exploited-vulnerabilities-catalog?field_cve=CVE-2017-11826
government-resource, us-government-resource

Sources

CVE List CVE-2017-11826
NVD CVE-2017-11826

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.