Overview
CVE-2026-20963 has been added to the CISA Known Exploited Vulnerabilities catalog. Published on January 13, 2026. Threat actors are actively exploiting this vulnerability in real-world attacks.
Deserialization of untrusted data in Microsoft Office SharePoint allows an unauthorized attacker to execute code over a network.
Threat Intelligence
| Metric | Value |
|---|---|
| CVE ID | CVE-2026-20963 |
| Severity | HIGH |
| CVSS Score | 0.0/10 |
| CISA KEV | ✅ Yes — Actively Exploited |
| KEV Date Added | March 18, 2026 |
| Remediation Deadline | March 21, 2026 |
| EPSS Score | 31.1% exploit probability |
| EPSS Percentile | Top 99% of all CVEs |
Why This Matters
This vulnerability has been added to the CISA Known Exploited Vulnerabilities (KEV) catalog, which means threat actors are actively exploiting it in real-world attacks.
Federal agencies are required to remediate by March 21, 2026. All organizations should treat this deadline as a strong recommendation.
Exploit Prediction (EPSS)
The FIRST EPSS model rates this vulnerability at 31.1% exploit probability (Moderate). This places it in the top 99% of all known CVEs by likelihood of exploitation in the next 30 days.
EPSS (Exploit Prediction Scoring System) uses real-world exploit data and machine learning to predict whether a vulnerability will be exploited. A high EPSS score is a strong signal to prioritize remediation.
Recommended Actions
- Verify exposure — Determine if your environment uses the affected software.
- Apply patches — Update to the latest version as soon as a fix is available.
- Monitor for compromise — Check logs for unusual activity.
- Meet the deadline — CISA recommends remediation by March 21, 2026.
References
CVE data aggregated from the National Vulnerability Database (NVD), CISA Known Exploited Vulnerabilities catalog, and FIRST EPSS. Analysis updated as new intelligence becomes available. Last updated: 2026-04-01.