CVE-2026-50517

Published Jul 24, 2026

Last updated 4 days ago

CVSS critical 9.9

Overview

Description
Deserialization of untrusted data in M365 Copilot allows an authorized attacker to execute code over a network.
Source
secure@microsoft.com
NVD status
Analyzed
CNA Tags
exclusively-hosted-service
Products
365_copilot

Risk scores

CVSS 3.1

Type
Secondary
Base score
9.9
Impact score
6
Exploitability score
3.1
Vector string
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Severity
CRITICAL

Weaknesses

secure@microsoft.com
CWE-502

Social media

Hype score
Not currently trending

  1. 🔒 #CyberSecurity CVE-2026-50517: M365 Copilot RCE via Deserialization — Defense and Hardening Gu… "Today, the NVD published CVE-2026-50517, assigning it a CVSS score of 9.9 (CRITICAL)." 🔗 https://t.co/ApjmTVFHab #CyberSecurity #ThreatIntel #cve202650517 #critical #c

    @SecurityAr58409

    24 Jul 2026

    57 Impressions

    0 Retweets

    0 Likes

    0 Bookmarks

    0 Replies

    0 Quotes

Configurations

Related CVEs

  1. Improper access control in Microsoft 365 Copilot for iOS allows an unauthorized attacker to elevate privileges over a network.•CVE-2026-58617
  2. Stack-based buffer overflow in Windows GDI allows an authorized attacker to elevate privileges locally.•CVE-2026-50387
  3. Improper neutralization of special elements used in a command ('command injection') in Copilot Chat (Microsoft Edge) allows an unauthorized attacker to execute code over a network.•CVE-2026-48561
  4. Url redirection to untrusted site ('open redirect') in M365 Copilot allows an unauthorized attacker to elevate privileges over a network.•CVE-2026-41106
  5. Url redirection to untrusted site ('open redirect') in Microsoft 365 Copilot's Business Chat allows an unauthorized attacker to elevate privileges over a network.•CVE-2026-47645

References

Sources include official advisories and independent security research.