Oh damn I had not seen the details of the MicroTik RCE: the client can send a public RSA key with correct N and e = 1 and the server will use it.
Two primitives/protocol things that would have prevented it: if RSA was defined with a fixed e, and if SSH clients sent a key hash instead.
https://github.com/advisories/GHSA-j9wg-77fw-f22f
Filippo Valsorda
npub1jz…yjnwm
2026-09-11 13:06:16 UTC
Author Public Key
npub1jzt0dcdqdhz0dmf3xk8fjn56kt45dqemtaz6rqzm9ycyz25p0nzqryjnwmSeen on
wss://relay.momostr.pinkPublished at
2026-09-11 13:06:16 UTCEvent JSON
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"created_at": 1789131976,
"kind": 1,
"tags": [
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"content": "Oh damn I had not seen the details of the MicroTik RCE: the client can send a public RSA key with correct N and e = 1 and the server will use it.\n\nTwo primitives/protocol things that would have prevented it: if RSA was defined with a fixed e, and if SSH clients sent a key hash instead.\n\nhttps://github.com/advisories/GHSA-j9wg-77fw-f22f",
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