CVE-2023-40012 uthenticode EKU validation bypass
Attackers can bypass Authenticode signature verification by using certificates not authorized for code signing, allowing malicious PE files to appear valid.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2023-40012?
CVE-2023-40012 is a medium-severity vulnerability in trailofbits uthenticode, published on 9 Aug 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
uthenticode is a small cross-platform library for partially verifying Authenticode digital signatures. Versions of uthenticode prior to the 2.x series did not check Extended Key Usages in certificates, in violation of the Authenticode X.509 certificate profile. As a result, a malicious user could produce a "signed" PE file that uthenticode would verify and consider valid using an X.509 certificate that isn't entitled to produce code signatures (e.g., a SSL certificate). By design, uthenticode does not perform full-chain validation. However, the absence of EKU validation was an unintended oversight. The 2.0.0 release series includes EKU checks. There are no workarounds to this vulnerability.
Which versions are affected by CVE-2023-40012?
It affects 1 product.
Products include Trailofbits Uthenticode.
How do I fix CVE-2023-40012?
No fix has been published for CVE-2023-40012 yet. Limit exposure of the affected software until one is available.
Is CVE-2023-40012 being exploited?
There is no known exploitation of CVE-2023-40012 in the wild and no public exploit code.
Other vulnerabilities in trailofbits uthenticode
Sources
Also known as GHSA-gm2f-j4rj-6xqj.