PuTTY's changelog from 2000 shows that PuTTYgen uses "the same RSA key file format as SSH 1" (the proprietary one, that predates OpenSSH). Reading and writing

PuTTY's changelog from 2000 shows that PuTTYgen uses "the same RSA key file format as SSH 1" (the proprietary one, that predates OpenSSH). Reading and writing OpenSSH-style keys came later (2012). https://www.chiark.greenend.org.uk/~sgtatham/putty/changes.html https://www.chiark.greenend.org.uk/~sgtatham/putty/changes.h...