cve/2023/CVE-2023-6237.md

### [CVE-2023-6237](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-6237)
![](https://img.shields.io/static/v1?label=Product&message=OpenSSL&color=blue)
![](https://img.shields.io/static/v1?label=Version&message=3.0.0%3C%203.0.13%20&color=brighgreen)
![](https://img.shields.io/static/v1?label=Vulnerability&message=Excessive%20Iteration&color=brighgreen)

### Description

Issue summary: Checking excessively long invalid RSA public keys may takea long time.Impact summary: Applications that use the function EVP_PKEY_public_check()to check RSA public keys may experience long delays. Where the key thatis being checked has been obtained from an untrusted source this may leadto a Denial of Service.When function EVP_PKEY_public_check() is called on RSA public keys,a computation is done to confirm that the RSA modulus, n, is composite.For valid RSA keys, n is a product of two or more large primes and thiscomputation completes quickly. However, if n is an overly large prime,then this computation would take a long time.An application that calls EVP_PKEY_public_check() and supplies an RSA keyobtained from an untrusted source could be vulnerable to a Denial of Serviceattack.The function EVP_PKEY_public_check() is not called from other OpenSSLfunctions however it is called from the OpenSSL pkey command lineapplication. For that reason that application is also vulnerable if usedwith the '-pubin' and '-check' options on untrusted data.The OpenSSL SSL/TLS implementation is not affected by this issue.The OpenSSL 3.0 and 3.1 FIPS providers are affected by this issue.

### POC

#### Reference
No PoCs from references.

#### Github
- https://github.com/GrigGM/05-virt-04-docker-hw
- https://github.com/chnzzh/OpenSSL-CVE-lib
- https://github.com/seal-community/patches