SB2021060830 - Privilege escalation in Microsoft Enhanced Cryptographic Provider

Description

This security bulletin contains information about 2 vulnerabilities.

1) Security restrictions bypass (CVE-ID: CVE-2021-31199)

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

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

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to improperly imposed security restrictions in Microsoft Enhanced Cryptographic Provider. A local user can bypass implemented security restrictions and read or modify otherwise restricted information.

Note, the vulnerability is being actively exploited in the wild and related to a zero-day vulnerability in Adobe Reader #VU53125 (CVE-2021-28550) patched on May 11.

2) Security restrictions bypass (CVE-ID: CVE-2021-31201)

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

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

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to improperly imposed security restrictions in Microsoft Enhanced Cryptographic Provider. A local user can bypass implemented security restrictions and read or modify otherwise restricted information.

Note, the vulnerability is being actively exploited in the wild and related to a zero-day vulnerability in Adobe Reader #VU53125 (CVE-2021-28550) patched on May 11.

Remediation

Install update from vendor's website.

References

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31199
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-31201