SB2025101467 - Multiple vulnerabilities in Microsoft Exchange Server

Description

This security bulletin contains information about 3 vulnerabilities.

1) Improper authentication (CVE-ID: CVE-2025-59249)

CWE-ID: CWE-287 - Improper Authentication

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:H/SI:H/SA:N/E:U/U:Green

The vulnerability allows a remote user to bypass authentication process.

The vulnerability exists due to usage of weak authentication process. A remote user can take over an admin account and use it to compromise mailboxes of other application users. 

2) Input validation error (CVE-ID: CVE-2025-59248)

CWE-ID: CWE-20 - Improper input validation

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green

The vulnerability allows a remote attacker to gain access to sensitive information. 

The vulnerability exists due to insufficient validation of user-supplied input. A remote attacker can perform spoofing attack and gain access to sensitive information.

3) Improper authentication (CVE-ID: CVE-2025-53782)

CWE-ID: CWE-287 - Improper Authentication

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear

The vulnerability allows a local user to bypass authentication process.

The vulnerability exists due to incorrect implementation of authentication process. A local user can execute arbitrary code with elevated privileges. 

Remediation

Install update from vendor's website.

References

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2025-59249
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2025-59248
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2025-53782