PuTTY 0.66 fixes security vulnerability (opens in new tab)

It may just mean nobody is looking at it.

I still don't understand why PuTTY got so popular (e.g. why not OpenSSH/Cygwin combo)

> signing the Putty executable

But there's a GPG signature file which you can use to verify the download! How? I wouldn't know because I've never bothered. And if I remember correctly, the RSA key is also 1024 bits which is another no-no (this has come up before).

See http://www.chiark.greenend.org.uk/~sgtatham/putty/keys.html

Also the.earth.li (PuTTY's download host) is available over HTTPS: https://the.earth.li/~sgtatham/putty/latest/x86/putty.exe

But I do agree that HTTPS on both by default would be great

http://www.9bis.net/kitty/ Is pretty nice and has updates

> To exploit a vulnerability in the terminal emulator, an attacker must be able to insert a carefully crafted escape sequence into the terminal stream. For a PuTTY SSH session, this must be before encryption, so the attacker likely needs access to the server you're connecting to. For instance, an attacker on a multi-user machine that you connect to could trick you into running cat on a file they control containing a malicious escape sequence. (Unix write(1) is not a vector for this, if implemented correctly.)

From the sounds of it, an attacker needs to either compromise the machine you intend to ssh into, or mitm before you first ever connect. Once keys are cached you should easily notice if you've been mitmed.

Seems like anyone with root on a server can compromise anyone who logs on to it using putty; e.g. by putting a payload in the motd or /etc/issue. Or setting the command prompt to something nefarious. Or putting something into log files that are cat'ed. Or even a regular account with access to put a log file somewhere, or using /wall. Or maybe a filename that is shown when using ls (like if you uploaded a file to a server and that file was stored with the name you entered as a user; this would require very carefully crafted shell code though).

All quite unlikely attack vectors and hard to pull off remotely, but I've seen exploits that looked harder from the outside.

Maybe you could trick the user into clicking on a link to "telnet:evilserver.example.com" and host a telnet-protocol-compatible TCP server on port 23 that just sends the payload without requiring any user login?

There's a phrase "get a round tuit" which is a phonetical approxmaton of "get around to it".

https://en.m.wiktionary.org/wiki/round_tuit

Looks like ed25519 was added in May 10th, 2015. [1]

     We claim version: SSH-2.0-PuTTY_Snapshot_2015_11_08.b003e5c
     Server version: SSH-2.0-OpenSSH_6.7p1 Debian-5
     Using SSH protocol version 2
     Doing ECDH key exchange with curve Curve25519 and hash SHA-256
     Host key fingerprint is:
     ssh-ed25519 256 <fingerprint>
     Initialised ChaCha20 client->server encryption
     Initialised Poly1305 client->server MAC algorithm (in ETM mode) (required by cipher)
     Initialised ChaCha20 server->client encryption
     Initialised Poly1305 server->client MAC algorithm (in ETM mode) (required by cipher)

I'm no expert, and this might not be what you are talking about, but to my untrained eye, it does?

Now, to get back on topic, they believe that the attack would already need access to the server.

"To exploit a vulnerability in the terminal emulator, an attacker must be able to insert a carefully crafted escape sequence into the terminal stream. For a PuTTY SSH session, this must be before encryption, so the attacker likely needs access to the server you're connecting to. For instance, an attacker on a multi-user machine that you connect to could trick you into running cat on a file they control containing a malicious escape sequence. (Unix write(1) is not a vector for this, if implemented correctly.)"

[1] http://tartarus.org/~simon-git/gitweb/?p=putty-wishlist.git;...

My favourite was the roguelike ADoM, which went up to 0.99, then alpha through gamma, then up to gamma 16, for a final version of 0.99gamma16 before tripping over to 1.0.

I'd also like to know this, but won't have time to check. There's also many many forks of PuTTY that'll need to be updated.

don't forget to restart, as well.

I think it was more like 1000...