highclosedpatched
Microsoft SharePoint Server: Microsoft SharePoint Server Deserialization of Untrusted Data Vulnerability
› Microsoft SharePoint Server
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- started
- Jul 1, 2026
- closed
- Jul 1, 2026
- CVEs
- 1
- sources
- 3
## summary
Microsoft SharePoint Server contains a deserialization of untrusted data vulnerability which allows an authorized attacker to execute code over a network. Added to CISA KEV on 2026-07-01.
severity: Actively exploited (CISA KEV); known ransomware use
## cve ids[1]
## affected
- See vendor advisory / CISA notes (versions not always listed in KEV feed)
## fixed in
- See vendor advisory linked in sources
## timeline[1]
CISA added CVE-2026-45659 to the KEV catalog (due 2026-07-04).
## advisories[3]
## notes & caveats
Derived from CISA KEV JSON feed catalogVersion 2026.10.21. Exact affected/fixed version strings are not always in the KEV record — verify against the vendor advisory URL. startedAt uses dateAdded (exploitation may have begun earlier).
