CVE-2026-50517
Medium
Elevated severity or exploit probability.
CVSS base
9.9
CRITICAL
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
EPSS — probability of exploitation (30 days)
1.3%
68.1th percentile
CISA KEV
Not listed
Weakness / dates
CWE-502
Published 2026-07-24 · modified 2026-07-29
CVSS breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
| Attack Vector | N | Network |
| Attack Complexity | L | Low |
| Privileges Required | L | Low |
| User Interaction | N | None |
| Scope | C | Changed |
| Confidentiality | H | High |
| Integrity | H | High |
| Availability | H | High |
Timeline
- 2026-07-24 — Published (NVD)
- 2026-07-29 — Last modified (NVD)
Description
Deserialization of untrusted data in M365 Copilot allows an authorized attacker to execute code over a network.