PatchTheCVECVE-2026-102866: Improper verification of cryptographic signature in Microsoft Office SharePoint allows an unauthorized attacke
CVE-2026-102866 is a high-severity flaw (CVSS 8.1) affecting sharepoint server. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
Improper verification of cryptographic signature in Microsoft Office SharePoint allows an unauthorized attacker to elevate privileges over a network.
Why this priority
- High severity
- Remotely exploitable, no login, no user action
- On your watchlist
A fixed release or distro patch exists.
Risk facts
| CVSS score | 8.1 (High) |
| Attack vector | Network (remote) |
| Attack complexity | High |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.7% (top 48%) |
| CISA exploited list | No |
| Weakness | CWE-347 |
| Published | 2026-10-13 |
| Last modified | 2026-10-14 |
Last updated 2026-10-14 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2026-102866?
sharepoint server: upgrade to 16.0.20326.20190. Exact commands for each OS are on this page.
Is CVE-2026-102866 being exploited?
CVE-2026-102866 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2026-102866 affect?
CVE-2026-102866 affects sharepoint server. Severity is high (CVSS 8.1). Improper verification of cryptographic signature in Microsoft Office SharePoint allows an unauthorized attacker to elevate privileges over a network.
How urgent is CVE-2026-102866?
Priority 51/100. High severity; Remotely exploitable, no login, no user action; On your watchlist
Software pages
SharePoint vulnerabilities · Microsoft Office vulnerabilities
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