How severe is CVE-2017-11826?

CVE-2017-11826 has a CVSS score of 7.8/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2017-11826?

Affected package information for CVE-2017-11826 is not yet fully mapped. Check the official advisory links for details.

How do I fix CVE-2017-11826?

No fixed release is recorded for CVE-2017-11826 yet. Track the upstream advisory, and apply the exposure-reduction steps below in the meantime.

How do I detect CVE-2017-11826 in my code and dependencies?

Identify every host running the affected component and compare the installed build against the fixed version below — for source-built or distro-packaged software the version string, not a lockfile, is the source of truth (`dpkg -l`, `rpm -q`, or the binary's own `--version`).

How do I mitigate CVE-2017-11826 if there is no patch (or I can't update yet)?

Constrain what reaches the vulnerable code: limit the size and shape of untrusted input, isolate the affected component in a sandboxed or least-privileged process, and enable the platform's memory-safety mitigations (ASLR, stack protector, hardened allocator) so an out-of-bounds access is more likely to fail closed than to be exploitable.

Is CVE-2017-11826 actively exploited in the wild?

Yes. There are 7 known exploit references for CVE-2017-11826, including 6 in-the-wild exploitations observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2017-11826?

CVE-2017-11826 has an EPSS (Exploit Prediction Scoring System) score of 81.3%, placing it in the 100th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. A score above 50% indicates significantly elevated exploitation risk — immediate patching is strongly recommended.

Is CVE-2017-11826 in the CISA Known Exploited Vulnerabilities catalog?

Yes. CVE-2017-11826 (Microsoft Office Remote Code Execution Vulnerability) was added to CISA's Known Exploited Vulnerabilities (KEV) catalog on 2022-03-03. CISA required all US federal civilian agencies to remediate this vulnerability by 2022-03-24. The required action was: Apply updates per vendor instructions. Being listed in the KEV catalog is the strongest possible confirmation of active exploitation — treat this as a critical priority.

What type of vulnerability is CVE-2017-11826?

CVE-2017-11826 is classified as Buffer Overflow (CWE-119). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2017-11826 published, and has it been updated?

CVE-2017-11826 was published on October 13, 2017 and was last updated on October 21, 2025. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🛡️

CISA KEV · ACTIVELY EXPLOITED

HIGH severity

CVE-2017-11826 — Microsoft

HIGH

CVE-2017-11826 is a high-severity (CVSS 7.8) Buffer Overflow vulnerability. It is in CISA's Known Exploited Vulnerabilities catalog (added 2022-03-03) — treat it as actively exploited and patch now. No vendor fix is recorded yet; mitigation options are listed below.

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,…

Published

Oct 13, 2017

Updated

Oct 21, 2025

Affected

7 products

Patched

See advisory

Exploits

7 known

Exploitation data as of Oct 23, 2026 · OSV.dev, NVD, CISA KEV, FIRST.org (EPSS)

Exploitation Status

Actively exploited in the wild

Confirmed by CISA's Known Exploited Vulnerabilities catalog on 2022-03-03. Federal agencies were required to remediate by 2022-03-24.
A successful exploit gives an attacker total control of the affected component, not partial access.

Exploitation and automatability from CISA (KEV catalog and SSVC triage) for CVE-2017-11826.

EPSS Exploitation Probability

via FIRST.org ↗

81.3%probability of exploitation in next 30 days

Very High Risk+0.18%

Lower risk than most CVEs100th percentile — riskier than 100% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

CVE-2017-11826 by exploitation likelihood (EPSS) against impact (CVSS). In the shaded patch-first corner (EPSS 50%+, CVSS 7.0+).

Where this sits among everything scored

Of 395,249 CVEs with a current EPSS score, this one falls in the 50–90% band (highlighted). Counts from FIRST.org, log-scaled.

Description

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.

Affected Products

7 products · 13 configurations

Application

office compatibility packmicrosoft

all

Application

office online servermicrosoft

1 version

2016

Application

office web apps servermicrosoft

2 versions

20102013

Application

office word viewermicrosoft

all

Application

sharepoint enterprise servermicrosoft

1 version

2016

Application

sharepoint servermicrosoft

2 versions

20102013

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.