topic Re: Disable weak ciphers on remote access clients? in SASE and Remote Access

Disable weak ciphers on remote access clients?

Danny — Mon, 15 Jan 2024 21:28:22 GMT

We hardened a customers' security gatway via cipher_util (sk126613) and disabled all weak ciphers to reach PCI DSS compliance. Then remote access clients (MacOS using visitor mode) failed to connect, so we opened a SR.

Check Point support advised to enable these three ciphers according to sk108426.

TLS_RSA_WITH_RC4_128_MD5
TLS_RSA_WITH_AES_128_CBC_SHA
TLS_RSA_WITH_AES_256_CBC_SHA

and noted:

It is best to keep the 3 ciphers on to avoid any issues regarding remote access/mobile access connectivity
Currently there is no ETA to whether the client will be on the same cipher suite as the GW itself.

Of course that doesn't satisfy our customer as it conflicts with PCI DSS requirements for strong ciphers, such as SHA-2.
Is there any other solution or workaround available?

Re: Disable weak ciphers on remote access clients?

the_rock — Mon, 15 Jan 2024 19:49:42 GMT

Hey Danny,

Guy in TAC told me while back that some of these settings in global properties may have something to do with it, but I never ended up testing it, so hard to say.

Andy

Re: Disable weak ciphers on remote access clients?

Martin_Schwarz — Tue, 16 Jan 2024 07:38:36 GMT

These are the settings for the IKE algorithms. So they should not impact how the IPsec traffic is tunneled over HTTPS in Visitor Mode. It seems like the Visitor Mode is part of the MultiPortal daemon (sk107852) and is therefore affected by the settings of the cipher_util.

Re: Disable weak ciphers on remote access clients?

the_rock — Tue, 16 Jan 2024 12:49:17 GMT

Thats true, thats why I found it a bit odd when TAC told me that was related to remote access, but maybe as it was under remote access section, not sure.

Andy

Re: Disable weak ciphers on remote access clients?

Timothy_Hall — Tue, 16 Jan 2024 15:01:05 GMT

You may find this SK helpful which details how to completely banish 3DES from being used in any part of the Check Point product including Remote Access VPN, Gaia Portal, management API, etc. This is mentioned in my Gateway Performance Optimization class as improving performance, but certainly improves security as well:

sk113114: Check Point response to CVE-2016-2183 (Sweet32)

Might be able to deconstruct the provided commands and banish SHA1 and other weak ciphers too.