Cryptographic issues in Microsoft products - #VU18788
Published: June 13, 2019
Vulnerability identifier: #VU18788
CSH Severity: Medium
CVSS v4: 8.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: N/A
CWE-ID: CWE-310
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to an error when calculating the modular inverse on specific bit patterns with bcryptprimitives!SymCryptFdefModInvGeneric() function when processing X.509 certificates. A remote attacker can supply a specially crafted X.509 certificate to the affected system and trigger denial of service conditions.
Any application that uses the vulnerable library, e.g. antivirus software is susceptible to this issue.
Affected software
SymCrypt
Microsoft Windows
Windows Server
Microsoft Windows
Windows Server
Remediation
Install updates from vendor's website.