Versions of the package yhirose/cpp-httplib before 0.12.4 are vulnerable to CRLF Injection when untrusted user input is used to set the content-type header in the HTTP .Patch, .Post, .Put and .Delete requests. This can lead to logical errors and other misbehaviors. **Note:** This issue is present due to an incomplete fix for [CVE-2020-11709](https://security.snyk.io/vuln/SNYK-UNMANAGED-YHIROSECPPHTTPLIB-2366507).

cpp-httplib through 0.5.8 does not filter \r\n in parameters passed into the set_redirect and set_header functions, which creates possibilities for CRLF injection and HTTP response splitting in some specific contexts.