CVE-2024-34702 Botan has a Denial of Service Due to Excessive Name Constraints
An attacker can cause a denial of service in Botan by presenting a certificate chain with excessive names and constraints, requiring an upgrade to patched versions.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2024-34702?
CVE-2024-34702 is a medium-severity denial of service vulnerability in randombit botan, published on 8 Jul 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Botan is a C++ cryptography library. X.509 certificates can identify elliptic curves using either an object identifier or using explicit encoding of the parameters. Prior to 3.5.0 and 2.19.5, checking name constraints in X.509 certificates is quadratic in the number of names and name constraints. An attacker who presented a certificate chain which contained a very large number of names in the SubjectAlternativeName, signed by a CA certificate which contained a large number of name constraints, could cause a denial of service. The problem has been addressed in Botan 3.5.0 and a partial backport has also been applied and is included in Botan 2.19.5.
Weakness: CWE-405
Which versions are affected by CVE-2024-34702?
How do I fix CVE-2024-34702?
Upgrade to a fixed version.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2024-34702 being exploited?
There is no known exploitation of CVE-2024-34702 in the wild and no public exploit code.
Sources
Also known as ALPINE-CVE-2024-34702, AZL-43942, AZL-44796, DEBIAN-CVE-2024-34702, GHSA-5gg9-hqpr-r58j, UBUNTU-CVE-2024-34702.