PuTTY 0.84 is released
Simon Tatham
anakin at pobox.com
Fri May 22 11:50:55 BST 2026
PuTTY version 0.84 is released
------------------------------
All the pre-built binaries, and the source code, are now available
from the PuTTY website at
https://www.chiark.greenend.org.uk/~sgtatham/putty/
0.84 fixes the following security vulnerabilities:
- Previous versions of PuTTY can be made to crash during SSH
connection startup, by a malicious server or a MITM attacker
substituting malicious data in the initial SSH key exchange. Two
different bugs allow the server to cause an assertion failure or a
double-free crash.
- If you use an old insecure connection protocol like Telnet, and
connect through a proxy server that requires you to enter a
password, then the whole Telnet connection was accidentally marked
with the 'trust sigil' that distinguishes prompts from PuTTY itself
from prompts sent by the server. This could conceivably have fooled
a user into believing a malicious server's phony request for your
proxy password.
0.84 has some new features:
- PuTTY now has the option to run a user-specified command before
making its main network connection. You could use this, for
example, to perform a port knock or other network operation that
temporarily opens the port you want to connect to.
- On Unix, PuTTY's terminal now supports displaying 'pre-edit text',
showing what you have typed so far while you're entering a
multi-key sequence that generates a single Unicode character.
0.84 also has various bug fixes:
- In the Unix version, you couldn't configure a certificate authority
for certified host keys using the GUI, unless you had first
manually created the directory where PuTTY stores the configuration.
- Fixed spurious error "Network error: Socket is not connected" when
connecting via an HTTP proxy that requires authentication.
- On Windows, if you disable cursor blinking systemwide in Control
Panel but have it turned on in PuTTY, PuTTY would blink the cursor
frantically.
- Improved support for running the Unix version on Wayland: pterm
won't crash when trying to stamp utmp, and a sensible default font
will be selected instead of complaining about trad X11 'fixed'
being missing.
Enjoy using PuTTY!
Cheers,
Simon
--
import hashlib; print((lambda p,q,g,y,r,s,m: (lambda w:(pow(g,int(hashlib.sha1(
m.encode('ascii')).hexdigest(),16)*w%q,p)*pow(y,r*w%q,p)%p)%q)(pow(s,q-2,q))==r
and s%q!=0 and m)(12342649995480866419, 2278082317364501, 1670428356600652640,
5398151833726432125, 645223105888478, 1916678356240619, "<anakin at pobox.com>"))
More information about the PuTTY-announce
mailing list