Security readout for executives and security teams
Plain-English summary
A crafted Office or Word document can make vulnerable Microsoft document-handling software run attacker-controlled code after user interaction. The affected list includes legacy Office, Word, SharePoint, Office Web Apps, and Office Online Server components. Because CISA KEV lists this CVE, unpatched systems handling documents need urgent attention.
Executive priority
Treat as urgent for any environment still running the listed legacy Microsoft document-processing products. Known exploitation and remote code execution potential justify accelerated patch verification and compensating controls.
Technical view
CVE-2017-11826 is a memory corruption remote code execution issue in Microsoft document and web document-processing components. CVSS 3.1 is 7.8, with low attack complexity, no privileges required, user interaction required, and high confidentiality, integrity, and availability impact. The issue maps to CWE-119.
Likely exposure
Exposure is most likely where legacy Microsoft Office, Word Viewer, Word Automation Services, SharePoint 2010, Office Web Apps Server, or Office Online Server process untrusted documents or user-supplied files.
Exploitation context
Active exploitation is supported by the CISA Known Exploited Vulnerabilities listing. Public references also discuss analysis and exploitation, but this assessment does not rely on or provide exploit procedure details.
Researcher notes
The supplied data identifies memory corruption in object handling, UI-required exploitation, and broad legacy product coverage. Evidence confirms KEV status, but product-specific fixed builds and detailed mitigations must be taken from Microsoft’s advisory.
Mitigation direction
- Apply the Microsoft security update or vendor guidance for CVE-2017-11826.
- Prioritize internet-facing or document-ingestion servers first.
- Retire unsupported Office, SharePoint, and Office Web Apps versions where possible.
- Restrict handling of untrusted Office documents until patched.
- Review email and file-upload controls for malicious document delivery.
Validation and detection
- Inventory affected Microsoft Office, Word, SharePoint, and Office web components.
- Confirm patch status against Microsoft’s CVE-2017-11826 advisory.
- Identify systems that automatically process uploaded or emailed documents.
- Check endpoint and server telemetry for suspicious document-triggered process activity.
- Verify KEV-driven remediation tracking includes this CVE.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-119: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2017-11826 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.8 (3.1)
- Known Exploited
- Yes
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CISA KEV status
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H1.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.8HighVector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2017-11826CVE reference · x_refsource_CONFIRM
- https://0patch.blogspot.com/2017/11/0patching-pretty-nasty-microsoft-word.htmlCVE reference · x_refsource_MISC
- https://www.tarlogic.com/en/blog/exploiting-word-cve-2017-11826/CVE reference · x_refsource_MISC
- https://securingtomorrow.mcafee.com/mcafee-labs/analyzing-microsoft-office-zero-day-exploit-cve-2017-11826-memory-corruption-vulnerability/CVE reference · x_refsource_MISC
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2017-11826CVE reference · government-resource
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Restriction of Operations within the Bounds of a Memory Buffer
Improper Restriction of Operations within the Bounds of a Memory Buffer represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.