CURL.SetOptionProxySSLVersion
-----------------------------

Sets which version of SSL/TLS to attempt to use for proxy.

| Component | Version | macOS | Windows | Linux | Server | iOS SDK |
|---|---|---|---|---|---|---|
| [CURL](component_CURL.md) | [8.2](newinversion82.md) | ✅ Yes | ✅ Yes | ✅ Yes | ✅ Yes | ✅ Yes |

MBS( "CURL.SetOptionProxySSLVersion"; curl; Value ) 

**MBS**( **"CURL.SetOptionProxySSLVersion";** /\* Sets which version of SSL/TLS to attempt to use for proxy. \*/  
**$curl**; /\* The CURL session handle. \*/   
**$Value**) /\* The option value. \*/ 

### Parameters

| Parameter | Description | Example |
|---|---|---|
| curl | The CURL session handle. | $curl |
| Value | The option value. |  |

### Result

Returns OK or error.

### Description

Sets which version of SSL/TLS to attempt to use for proxy.   
The SSL and TLS versions have typically developed from the most insecure version to be more and more secure in this order through history: SSL v2, SSLv3, TLS v1.0, TLS v1.1, TLS v1.2 and the most recent TLS v1.3.  
  
Use one of the available defines for this purpose. The available options are:  
  
| Default | 0 | The default acceptable version range. The minimum acceptable version is by default TLS v1.0 since 7.39.0 (unless the TLS library has a stricter rule). |
|---|--:|---|
| TLSv1 | 1 | TLS v1.0 or later |
| SSLv2 | 2 | SSL v2 (but not SSLv3) |
| SSLv3 | 3 | SSL v3 (but not SSLv2) |
| TLSv1.0 | 4 | TLS v1.0 or later (Added in 7.34.0) |
| TLSv1.1 | 5 | TLS v1.1 or later (Added in 7.34.0) |
| TLSv1.2 | 6 | TLS v1.2 or later (Added in 7.34.0) |
| TLSv1.3 | 7 | TLS v1.3 or later (Added in 7.52.0) |

  
See also kSSLVersion\* constants.  
  
The maximum TLS version can be set by using one of the CURL\_SSLVERSION\_MAX\_ macros below. It is also possible to OR one of the CURL\_SSLVERSION\_ macros with one of the CURL\_SSLVERSION\_MAX\_ macros.   
  
| Default | 65536 | The flag defines the maximum supported TLS version by libcurl, or the default value from the SSL library is used. libcurl will use a sensible default maximum, which was TLS v1.2 up to before 7.61.0 and is TLS v1.3 since then - assuming the TLS library support it. (Added in 7.54.0) |
|---|--:|---|
| Max TLSv1.0 | 262144 | The flag defines maximum supported TLS version as TLS v1.0. (Added in 7.54.0) |
| Max TLSv1.1 | 327680 | The flag defines maximum supported TLS version as TLS v1.1. (Added in 7.54.0) |
| Max TLSv1.2 | 393216 | The flag defines maximum supported TLS version as TLS v1.2. (Added in 7.54.0) |
| Max TLSv1.3 | 458752 | The flag defines maximum supported TLS version as TLS v1.3. (Added in 7.54.0) |

  
Please note that MBS Plugin does support TLS v1.3 since end of 2018.  
See also [PROXY\_SSLVERSION](https://curl.haxx.se/libcurl/c/CURLOPT_PROXY_SSLVERSION.html) option in CURL manual.

### See also

- [CURL.SetOptionProxySSLCert](CURLSetOptionProxySSLCert.md)
- [CURL.SetOptionProxySSLCertBlob](CURLSetOptionProxySSLCertBlob.md)
- [CURL.SetOptionProxySSLKey](CURLSetOptionProxySSLKey.md)
- [CURL.SetOptionProxySSLKeyBlob](CURLSetOptionProxySSLKeyBlob.md)
- [CURL.SetOptionProxySSLKeyType](CURLSetOptionProxySSLKeyType.md)
- [CURL.SetOptionProxySSLOptions](CURLSetOptionProxySSLOptions.md)
- [CURL.SetOptionProxySSLVerifyHost](CURLSetOptionProxySSLVerifyHost.md)
- [CURL.SetOptionProxySSLVerifyPeer](CURLSetOptionProxySSLVerifyPeer.md)
- [CURL.SetOptionProxyUsername](CURLSetOptionProxyUsername.md)
- [CURL.SetOptionSSLVersion](CURLSetOptionSSLVersion.md)

Created 15th April 2018 , last changed 23th February 2021

  
[CURL.SetOptionProxySSLVerifyPeer](CURLSetOptionProxySSLVerifyPeer.md) - [CURL.SetOptionProxyServiceName](CURLSetOptionProxyServiceName.md)

[HTML Version](CURLSetOptionProxySSLVersion.shtml)