CVE-2026-20963
Confirmed PUBLISHEDMicrosoft SharePoint Remote Code Execution Vulnerability
1 day faster than CISA KEV
Recommended Action
Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
At a Glance
Deserialization of untrusted data in Microsoft Office SharePoint allows an unauthorized attacker to execute code over a network.
- CVE Published
- Jan 13, 2026
- Exploitation Reported
- Jun 01, 2026
- CVSS
- 9.8 Critical
- EPSS
- 31.1%
Affected Versions
| Vendor | Product | Version | Status |
|---|---|---|---|
| Microsoft |
Microsoft SharePoint Enterprise Server 2016
|
16.0.0 to < 16.0.5535.1001 |
Affected |
| Microsoft |
Microsoft SharePoint Server 2019
|
16.0.0 to < 16.0.10417.20083 |
Affected |
| Microsoft |
Microsoft SharePoint Server Subscription Edition
|
16.0.0 to < 16.0.19127.20442 |
Affected |
CVE References
- Microsoft SharePoint Remote Code Execution Vulnerability msrc.microsoft.com · Vendor Advisory https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20963
Recommended Actions
- Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.
- Check enrichment artifacts for scanner coverage and available PoCs before rolling remediation validation.
- Use the Pro API to automate enrichment, telemetry, and workflow delivery for VM, SOC, and CTI pipelines.
Known Exploited Vulnerability Sources
Catalogues that list this CVE as a known exploited vulnerability.
Per-source evidence links for KEV attestations are available through the KEVIntel Pro API.
Learn about Pro API access| Source | Added |
|---|---|
| CVE First | 2026-06-01 12:10 UTC |
| CISA | 2026-06-02 14:02 UTC |
No detection artifacts or sensor request patterns are available for this CVE yet.
Check back as sensor telemetry and scanner integrations are updated.
Virtual Patch
Compensating WAF rules to help reduce exposure to this CVE. Rule content and deployable vendor exports are available with KEVIntel Enterprise.
KEVIntel does not currently have a virtual patch for this CVE. When available, KEVIntel virtual patches ship as deployable ModSecurity, Cloudflare, and AWS WAF rules.
Enterprise feature. Virtual patch rule content and deployable vendor exports (ModSecurity, Cloudflare, AWS WAF) are available to KEVIntel Enterprise users.
CVSS Scores
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Exploitation Status
Exploited in the wild
Recorded 2026-06-01 12:10:26 UTC · CVE
Proof of concept available
Recorded 2026-03-27 21:03:46 UTC · GitHub
Weaknesses (CWE)
-
Deserialization of Untrusted Data
Potential Proof of Concepts
These PoCs are unverified and could contain malware. Use at your own risk.
github · Created 2026-03-27 21:03:46 UTC · 1 stars
Timeline
Key exploitation, disclosure, scanner coverage, and KEV attestation events for this CVE.
-
14:02 UTC about 2 months ago14:02 UTC · about 2 months ago
Added to CISA KEV
Listed in the CISA Known Exploited Vulnerabilities catalog
-
12:10 UTC about 2 months ago12:10 UTC · about 2 months ago
Added to KEVIntel KEV Feed
High-confidence, third-party attested exploitation
-
21:03 UTC 4 months ago21:03 UTC · 4 months ago
Public PoC available
Public proof-of-concept code published
-
17:56 UTC 6 months ago17:56 UTC · 6 months ago
CVE published
Vulnerability disclosed publicly
-
20:04 UTC 8 months ago20:04 UTC · 8 months ago
CVE ID reserved
Identifier reserved by the CNA
Automate This Intelligence with the Pro API
Confidence scoring, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.
Pro API Example
GET /api/v2/pro/kevs/CVE-2026-20963
{
"cve_id": "CVE-2026-20963",
"title": "Microsoft SharePoint Remote Code Execution Vulnerability",
"affected_vendor": "Microsoft",
"affected_product": "Microsoft SharePoint Enterprise Server 2016, Microsoft SharePoint Server 2019, Microsoft SharePoint Server Subscription Edition",
"affected_versions": [
{ "vendor": "...", "product": "...", "status": "affected", "display_label": "..." }
],
"confidence": "Confirmed",
"cvss_score": 9.8,
"epss_score": 0.31109,
"exploit_status": {
"exploited_in_the_wild": true,
"active_exploitation_observed": false
},
"sensor_telemetry": { "...": "Pro API fields" },
"proof_of_concepts": [ "..." ],
"scanner_integrations": [ "..." ]
}