CVE-2025-64666
HighCVSS 7.5Exploitation Probability (EPSS)
Elevated risk58th percentile - higher than 58% of all known CVEs
Summary
Improper input validation in Microsoft Exchange Server allows an authorized attacker to elevate privileges over a network.
Risk Assessment
An attacker with appropriate permissions may gain elevated privileges, potentially leading to serious security breaches within the organization.
Recommendation
It is recommended to update Microsoft Exchange Server to the latest version to patch this vulnerability and implement additional security measures.
Other vulnerabilities in Microsoft Exchange Server
See all- CVE-2026-87696High
Improper verification of cryptographic signature in Microsoft Exchange Server allows an authorized attacker to elevate privileges over a network.
- CVE-2026-87695High
A vulnerability in Microsoft Exchange Server involves inclusion of functionality from an untrusted control sphere. An authorized attacker can elevate privileges locally.
- CVE-2026-87692High
A deserialization of untrusted data vulnerability in Microsoft Exchange Server allows an authorized attacker to elevate privileges locally.
- CVE-2026-77910High
Incorrect authorization in Microsoft Exchange Server allows an authorized attacker to elevate privileges over a network.
- CVE-2026-70571High
Stack-based buffer overflow in Microsoft Exchange Server allows an unauthorized attacker to execute code over a network.
- CVE-2026-70279Critical
Improper neutralization of input during web page generation (cross-site scripting) in Microsoft Exchange Server allows an unauthorized attacker to perform spoofing over a network.
- CVE-2026-69641Critical
Missing authorization in Microsoft Exchange Server allows an authorized attacker to elevate privileges over a network.
- CVE-2026-69356Critical
Improper neutralization of input during web page generation ('cross-site scripting') in Microsoft Exchange Server allows an unauthorized attacker to perform spoofing over a network.
- CVE-2026-55008Critical
A cross-site scripting (XSS) vulnerability in Microsoft Exchange Server allows an unauthorized attacker to perform spoofing over a network. The flaw is due to improper neutralization of input during web page generation.
- CVE-2026-45502Medium
A Server-Side Request Forgery (SSRF) vulnerability in Microsoft Exchange Server allows an authorized attacker to disclose information over a network.
Original NVD description (English source)
Improper input validation in Microsoft Exchange Server allows an authorized attacker to elevate privileges over a network.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS