November 13, 2026 Follow Egret
CVE-2026-20963 · CVE record: PUBLISHED

Microsoft SharePoint Remote Code Execution Vulnerability

Microsoft Microsoft SharePoint Enterprise Server 2016, Microsoft Microsoft SharePoint Server 2019, Microsoft Microsoft SharePoint Server Subscription Edition

Deserialization of untrusted data in Microsoft Office SharePoint allows an unauthorized attacker to execute code over a network.

Exploitation evidence

Known exploited · CISA KEV listed

Added 2026-03-18. Ransomware campaign use: Unknown.

CISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

CISA due date: 2026-03-21. This is the catalog’s deadline, not an assessment of your organization’s exposure.

KEV checked 13 Nov 2026, 00:20 Jerusalem · Original catalog ↗

Reported products and versions

Microsoft / Microsoft SharePoint Enterprise Server 2016

Default status: Not specified

  • affected: 16.0.0 to < 16.0.5535.1001 (custom)

Microsoft / Microsoft SharePoint Server 2019

Default status: Not specified

  • affected: 16.0.0 to < 16.0.10417.20083 (custom)

Microsoft / Microsoft SharePoint Server Subscription Edition

Default status: Not specified

  • affected: 16.0.0 to < 16.0.19127.20442 (custom)

Fixes and workarounds

No explicit solution text in the downloaded CVE record. Consult the vendor advisory; unaffected version ranges are shown above as reported, not inferred as a patch recommendation.

Sources and related reporting

CVE Program record ↗ · Download tracked evidence as JSON

Observed change timeline

History begins when Egret first downloads each source. It is not the complete upstream CVE history.

12 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-12",
  "epss": 0.29201,
  "percentile": 0.98199
}
10 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-10",
  "epss": 0.29201,
  "percentile": 0.98187
}
09 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-09",
  "epss": 0.29201,
  "percentile": 0.98185
}
08 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-08",
  "epss": 0.29201,
  "percentile": 0.98185
}
07 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-07",
  "epss": 0.29201,
  "percentile": 0.98184
}
06 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-06",
  "epss": 0.29201,
  "percentile": 0.98181
}
06 Nov 2026, 06:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-05",
  "epss": 0.29201,
  "percentile": 0.9818
}
04 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-04",
  "epss": 0.29201,
  "percentile": 0.98178
}
03 Nov 2026, 18:20 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-03",
  "epss": 0.29201,
  "percentile": 0.98175
}
03 Nov 2026, 12:20 Jerusalem · CVE Program record changed

Stored CNA snapshot at this observation.

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-20963",
                "options": [
                  {
                    "Exploitation": "active"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-01-08T00:00:00+00:00",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          },
          {
            "other": {
              "content": {
                "dateAdded": "2026-03-18",
                "reference": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20963"
              },
              "type": "kev"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-04-02T03:55:34.121Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "government-resource"
            ],
            "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-20963"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "platforms": [
            "x64-based Systems"
          ],
          "product": "Microsoft SharePoint Enterprise Server 2016",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "16.0.5535.1001",
              "status": "affected",
              "version": "16.0.0",
              "versionType": "custom"
            }
          ]
        },
        {
          "platforms": [
            "x64-based Systems"
          ],
          "product": "Microsoft SharePoint Server 2019",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "16.0.10417.20083",
              "status": "affected",
              "version": "16.0.0",
              "versionType": "custom"
            }
          ]
        },
        {
          "platforms": [
            "x64-based Systems"
          ],
          "product": "Microsoft SharePoint Server Subscription Edition",
          "vendor": "Microsoft",
          "versions": [
            {
              "lessThan": "16.0.19127.20442",
              "status": "affected",
              "version": "16.0.0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:microsoft:sharepoint_server_2016:*:*:*:*:enterprise:*:*:*",
                  "versionEndExcluding": "16.0.5535.1001",
                  "versionStartIncluding": "16.0.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:a:microsoft:sharepoint_server_2019:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "16.0.10417.20083",
                  "versionStartIncluding": "16.0.0",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:a:microsoft:sharepoint_server:*:*:*:*:subscription:*:*:*",
                  "versionEndExcluding": "16.0.19127.20442",
                  "versionStartIncluding": "16.0.0",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "datePublic": "2026-01-13T16:00:00.000Z",
      "descriptions": [
        {
          "lang": "en-US",
          "value": "Deserialization of untrusted data in Microsoft Office SharePoint allows an unauthorized attacker to execute code over a network."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 9.8,
            "baseSeverity": "CRITICAL",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en-US",
              "value": "GENERAL"
            }
          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-502",
              "description": "CWE-502: Deserialization of Untrusted Data",
              "lang": "en-US",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-07-30T20:47:08.605Z",
        "orgId": "f38d906d-7342-40ea-92c1-6c4a2c6478c8",
        "shortName": "microsoft"
      },
      "references": [
        {
          "name": "Microsoft SharePoint Remote Code Execution Vulnerability",
          "tags": [
            "vendor-advisory",
            "patch"
          ],
          "url": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20963"
        }
      ],
      "title": "Microsoft SharePoint Remote Code Execution Vulnerability"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "f38d906d-7342-40ea-92c1-6c4a2c6478c8",
    "assignerShortName": "microsoft",
    "cveId": "CVE-2026-20963",
    "datePublished": "2026-01-13T17:56:49.798Z",
    "dateReserved": "2025-12-04T20:04:16.341Z",
    "dateUpdated": "2026-07-30T20:47:08.605Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}
03 Nov 2026, 02:22 Jerusalem · EPSS observation updated

Stored EPSS snapshot at this observation.

{
  "date": "2026-11-02",
  "epss": 0.29201,
  "percentile": 0.98172
}
03 Nov 2026, 02:22 Jerusalem · CISA KEV status changed

Stored KEV snapshot at this observation.

{
  "cveID": "CVE-2026-20963",
  "cwes": [
    "CWE-502"
  ],
  "dateAdded": "2026-03-18",
  "dueDate": "2026-03-21",
  "forensicTriage": "No",
  "knownRansomwareCampaignUse": "Unknown",
  "notes": "https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20963 ; https://nvd.nist.gov/vuln/detail/CVE-2026-20963",
  "product": "SharePoint",
  "requiredAction": "Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.",
  "shortDescription": "Microsoft SharePoint contains a deserialization of untrusted data vulnerability that allows an unauthorized attacker to execute code over a network.",
  "vendorProject": "Microsoft",
  "vulnerabilityName": "Microsoft SharePoint Deserialization of Untrusted Data Vulnerability"
}
Egret — Back to top Egret