- Description
- Deserialization of untrusted data in Microsoft Office SharePoint allows an unauthorized attacker to execute code over a network.
- Source
- secure@microsoft.com
- NVD status
- Analyzed
- Products
- sharepoint_server
CVSS 3.1
- Type
- Secondary
- Base score
- 9.8
- Impact score
- 5.9
- Exploitability score
- 3.9
- Vector string
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Severity
- CRITICAL
Data from CISA
- Vulnerability name
- Microsoft SharePoint Deserialization of Untrusted Data Vulnerability
- Exploit added on
- Jul 16, 2026
- Exploit action due
- Jul 19, 2026
- Required action
- Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
- secure@microsoft.com
- CWE-502
- Hype score
- Not currently trending
🛡️We added Fortinet FortiSandbox vulnerabilities CVE-2026-25089 & CVE-2026-39808 and Microsoft SharePoint vulnerability CVE-2026-58644 to our KEV Catalog. Visit https://t.co/myxOwap1Tf & apply mitigations to protect your org from cyberattacks. #Cybersecurity #InfoSec
@CISACyber
16 Jul 2026
3113 Impressions
3 Retweets
10 Likes
2 Bookmarks
1 Reply
0 Quotes
CVE-2026-58644: SharePoint Server deserialization RCE (CVSS 9.8). Unauthenticated, network-exploitable. Sibling CVE demoed at Pwn2Own Berlin. Same July 14 patches as KEV-listed CVE-2026-56164. Investigation workflow → https://t.co/XV8bU4m3Ph
@hellorecon
15 Jul 2026
9 Impressions
0 Retweets
0 Likes
0 Bookmarks
0 Replies
0 Quotes
Running SharePoint? There are at least 4 vulns you want to pay attention to: CVE-2026-55040, CVE-2026-52522, CVE-2026-58644, CVE-2026-56164 unauthenticated RCE, exploits available etc. https://t.co/9moTd0gNju
@theluemmel
15 Jul 2026
2063 Impressions
2 Retweets
16 Likes
8 Bookmarks
2 Replies
0 Quotes
🔒 #CyberSecurity CVE-2026-58644: Microsoft SharePoint Deserialization RCE — Detection and Harden… "CVE-2026-58644 represents a significant escalation in risk for enterprises relying on…" 🔗 https://t.co/vl0JucLagR #CyberSecurity #ThreatIntel #cve202658644 #critical
@SecurityAr58409
15 Jul 2026
46 Impressions
0 Retweets
0 Likes
0 Bookmarks
0 Replies
0 Quotes
[
{
"nodes": [
{
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]