D4Stiny

**Name of the Vulnerable Software and Affected Versions** uthenticode version 1.0.9 **Description** uthenticode is a small cross-platform library for partially verifying Authenticode digital signatures. Version 1.0.9 of uthenticode hashed the entire file rather than hashing sections by virtual address, in violation of the Authenticode specification. As a result, an attacker could modify code within a binary without changing its Authenticode hash, making it appear valid from uthenticode's perspective. By design, uthenticode does not perform full-chain validation. However, the malleability of signature verification introduced in 1.0.9 was an unintended oversight. **Recommendations** For uthenticode version 1.0.9, upgrade to a version in the 2.x series to address the vulnerability. At the moment, there is no information about other versions that contain a fix for this vulnerability.

**Name of the Vulnerable Software and Affected Versions** uthenticode versions prior to 2.x **Description** The issue concerns uthenticode, a library for partially verifying Authenticode digital signatures. It does not check Extended Key Usages in certificates, which is against the Authenticode X.509 certificate profile. This allows a malicious user to create a "signed" PE file that uthenticode would verify as valid, using an X.509 certificate not meant for code signatures, such as a SSL certificate. The library does not perform full-chain validation by design, but the lack of EKU validation was an oversight. The 2.0.0 release series includes EKU checks. **Recommendations** For versions prior to 2.x, update to the 2.0.0 release series or later to include EKU checks. At the moment, there is no information about other workarounds for this issue.