CVE-2017-11826
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.
- CVSS
- 7.8Highscored by CISA
- Exploited in the wild
- Yes, in CISA KEV since 3 Mar 2022CISA deadline for US federal agencies: 24 Mar 2022unvetted proof-of-concept code on github
- EPSS
- 82.2%chance of exploitation in the next 30 daystop 0.4% of scored CVEsFIRST score of 11 Nov 2026
- Fix
- Patch availablesee the advisories in the references
- Published
- 13 Oct 2017analysed here 12 Nov 2026
Do first. Apply updates per vendor instructions. (CISA's required action for this KEV entry)
Summary
Triage
The summary, impact and action text on this page are written by our AI analysis pipeline, or taken from the NVD description when a CVE was imported from NVD. They are not the vendor's wording: check them against the sources. A longer AI executive summary and technical analysis are generated for signed-in accounts on the Max plan.
Affected products
| Product | Affected versions | Vendor says fixed in |
|---|---|---|
| Microsoft Corporation Microsoft Office | 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, Office Online Server.Vendor says fixed in: not stated |
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.
Products named in our analysis
- microsoft:office_compatibility_pack
- microsoft:office_online_server
- microsoft:office_web_apps_server
- microsoft:office_word_viewer
- microsoft:sharepoint_enterprise_server
- microsoft:sharepoint_server
- microsoft:word
Fix and mitigation
WAF and other mitigations
Can a WAF block it? No. The attack needs local access to the machine, so a WAF is not on its path.
Also consider: patch
Based on the attack vector (local or physical access). We check Cloudflare, AWS, Google Cloud Armor and Azure; for Akamai, Imperva, Fastly, F5, ask your vendor.
Remediation steps (AI-written)
Step-by-step remediation is generated for accounts on the Max plan, for CVEs that match a technology in their stack. Add this technology to your stack to see the fix checklist.
Exploitation evidence
- CISA KEV catalog
- Listed since 3 Mar 2022.
- CISA due date
- 24 Mar 2022, the remediation deadline for US federal agencies
- CISA required action
- Apply updates per vendor instructions.
- Public exploit code
- Unvetted proof-of-concept code on GitHub: 1 GitHub proof of concept
- CISA SSVC
- exploitation active, automatable no, technical impact totalAssessed by CISA 10 Feb 2025 (SSVC 2.0.3). Exploitation is none, poc (public proof of concept) or active.
GitHub proofs of concept
- thatskriptkid/CVE-2017-118268 stars
Listed so you can judge urgency, not as a recommendation to run anything. GitHub “proofs of concept” are unvetted: some are fake or carry malware. Exploit-DB marks the entries its staff verified.
Timeline
- 13 Oct 2017Published
- 9 Feb 2018First proof-of-concept repository on GitHub (unvetted)118 days (about 4 months) later
- 3 Mar 2022Added to CISA KEV (exploited in the wild)1,483 days (about 4 years) later
- 24 Mar 2022CISA remediation due date (US federal agencies)21 days later
- 10 Feb 2025CISA SSVC assessment: exploitation active1,055 days (about 3 years) later
- 21 Oct 2025CVE record last updated253 days (about 8 months) later
- 12 Nov 2026Analysed by vulneraibility.com387 days (about 1 year) later
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
| Metric | Value | What it means |
|---|---|---|
| Attack vector | LocalLocal access required (shell, logged-in user). | Local access required (shell, logged-in user). |
| Attack complexity | LowRepeatable attack, no special conditions. | Repeatable attack, no special conditions. |
| Privileges required | NoneThe attacker needs no prior access. | The attacker needs no prior access. |
| User interaction | RequiredA victim must click, open or otherwise cooperate. | A victim must click, open or otherwise cooperate. |
| Scope | UnchangedImpact stays within the vulnerable component. | Impact stays within the vulnerable component. |
| Confidentiality | HighTotal data disclosure possible. | Total data disclosure possible. |
| Integrity | HighComplete modification possible. | Complete modification possible. |
| Availability | HighFull outage possible. | Full outage possible. |
Common questions
Is CVE-2017-11826 being exploited?
Yes. CVE-2017-11826 appears in CISA's Known Exploited Vulnerabilities catalog, which means exploitation in the wild has been confirmed and reported. Treat it as active rather than theoretical, and patch it ahead of higher-scoring vulnerabilities that carry no exploitation evidence.
How severe is CVE-2017-11826?
CVE-2017-11826 is rated High with a CVSS score of 7.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2017-11826?
Yes. A fix has been recorded for CVE-2017-11826. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2017-11826 affect?
CVE-2017-11826 affects microsoft:office_compatibility_pack, microsoft:office_online_server, microsoft:office_web_apps_server, microsoft:office_word_viewer, and 3 further products or versions. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
References
7 references in the CVE record, grouped by the tags the record gives them.
Other links (7)
- portal.msrc.microsoft.com /en-US/security-guidance/advisory/CVE-2017-11826
- 0patch.blogspot.com /2017/11/0patching-pretty-nasty-microsoft-word.html
- securityfocus.com /bid/101219
- tarlogic.com /en/blog/exploiting-word-cve-2017-11826/
- securitytracker.com /id/1039541
- securingtomorrow.mcafee.com /mcafee-labs/analyzing-microsoft-office-zero-day-exploit-cve-2017-11826-memory-c
Show 1 more
- cisa.gov /known-exploited-vulnerabilities-catalog?field_cve=CVE-2017-11826
Where the data on this page comes from
- CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
- NVD: CVSS and CPE data
- CISA KEV catalog: exploitation, date added, due date
- CISA Vulnrichment (ADP): SSVC decision points
- FIRST EPSS: exploit probability and percentile
- PoC-in-GitHub: GitHub repositories that claim a proof of concept
Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.
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