Home » Computer » 這次 PKCS #1 1.5 的 ROBOT 攻擊,Cisco 沒打算修...

1998 年就發現的 security issue 因為 workaround 也很複雜,所以不是每一家都修對方法,於是 19 年後又被爆破了。這次叫做 ROBOT:「1998 attack that messes with sites’ secret crypto keys is back in a big way」。

可以看到中獎的表:

這次的攻擊在 client 端無法修正,只能在 server 端修正:

Do I need to update my browser?
No. This is an implementation bug in servers, there is nothing clients can do to prevent it.

如果 server 端無法盡快修正的話,想辦法避開 RSA encryption 可以躲開這個問題,而且因為現代瀏覽器都有非 RSA 的替代方案,這樣做應該都還有退路,可以維持連線的可能性:

Disable RSA encryption!
ROBOT only affects TLS cipher modes that use RSA encryption. Most modern TLS connections use an Elliptic Curve Diffie Hellman key exchange and need RSA only for signatures. We believe RSA encryption modes are so risky that the only safe course of action is to disable them. Apart from being risky these modes also lack forward secrecy.

但使用 Cisco ACE 就哭了,因為 Cisco ACE 只支援 RSA encryption,而 Cisco 官方以產品線已經關閉,不再提供維護而沒有提供更新的計畫,所以就進入一個死胡同...

不過 Cisco 自己也還在用 Cisco ACE 就是了,不在意就不會痛的感覺 XD

I have a Cisco ACE device.
Cisco informed us that the ACE product line was discontinued several years ago and that they won't provide an update. Still, we found plenty of vulnerable hosts that use these devices.

These devices don't support any other cipher suites, therefore disabling RSA is not an option. To our knowledge it is not possible to use these devices for TLS connections in a secure way.

However, if you use these products you're in good company: As far as we can tell Cisco is using them to serve the cisco.com domain.

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