An ssh server would exploit a vulnerability in the ssh client when it connects.
For example, openssh has both a client and server. There’s been vulnerabilities in openssh, in the client. Those vulnerabilities aren’t reachable unless you’re connecting to a server attempting to exploit you, so the risk is quite low because you know and trust most servers you’re connecting to with ssh.
To sum it up: Connecting to this server is probably fine, but in doing so most people are doing something significantly riskier without realizing it.
There has never been a real-world OpenSSH exploit that allows a server to RCE a client that connected to it without a bunch of dubious qualifiers. Connecting to a random SSH server is much, much less dangerous than running a random binary or executing a random curl install script, both of which people do all the time, and is probably about on par with the likelihood of a random website escaping your browser's sandbox and RCEing you.
I believe the recent cve-2026-55200 in libssh2 (client-side library) was allowing exactly this.
<a href="https://nvd.nist.gov/vuln/detail/cve-2026-55200" rel="nofollow">https://nvd.nist.gov/vuln/detail/cve-2026-55200
("Remote attackers can send crafted SSH packets with excessively large packet_length values to corrupt heap memory and achieve remote code execution.")
Of course the other abouts that you whatted (such as random curl install scripts, binaries, etc.) are still more dangerous.
3dedb728-3f77 · · focus · HN ↗
People understand that reverse hacking can happen when connecting to random ssh server, right?
scubbo · · focus · HN ↗
No, actually, I've never heard of such a vector. How would that work?
jerrythegerbil · · focus · HN ↗
For example, openssh has both a client and server. There’s been vulnerabilities in openssh, in the client. Those vulnerabilities aren’t reachable unless you’re connecting to a server attempting to exploit you, so the risk is quite low because you know and trust most servers you’re connecting to with ssh.
To sum it up: Connecting to this server is probably fine, but in doing so most people are doing something significantly riskier without realizing it.
applfanboysbgon · · focus · HN ↗
soblemprolver · · focus · HN ↗
Of course the other abouts that you whatted (such as random curl install scripts, binaries, etc.) are still more dangerous.
fulafel · · focus · HN ↗
soblemprolver · · focus · HN ↗
fulafel · · focus · HN ↗