From anakin at pobox.com Mon Apr 15 20:18:34 2024 From: anakin at pobox.com (Simon Tatham) Date: Mon, 15 Apr 2024 20:18:34 +0100 Subject: PuTTY 0.81 is released Message-ID: <1713208675-sup-6254@thyestes.tartarus.org> PuTTY version 0.81 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/ This is a SECURITY UPDATE. We recommend that _everybody_ upgrade, as soon as possible. Additionally, if you have any 521-bit ECDSA private keys that you've used with PuTTY, you should consider them to be compromised: generate new keys, and remove the old public keys from any authorized_keys files. The only change between 0.80 and 0.81 is one security fix: - ECDSA signatures using 521-bit keys (the NIST P521 curve, otherwise known as ecdsa-sha2-nistp521) were generated with biased random numbers. This permits an attacker in possession of a few dozen signatures to RECOVER THE PRIVATE KEY. Any 521-bit ECDSA private key that PuTTY or Pageant has used to sign anything should be considered compromised. This vulnerability has the identifier CVE-2024-31497. Enjoy using PuTTY! -- 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, ""))