From b1697b649aa9cac68a35b3bf0f3ab433f5bbf1dc Mon Sep 17 00:00:00 2001 From: Ed Maste Date: Tue, 18 Feb 2025 22:00:45 -0500 Subject: [PATCH] ssh: Don't reply to PING in preauth phase or during KEX Obtained from: OpenSSH 5e07dee272c3 Security: CVE-2025-26466 Security: FreeBSD-SA-25:05.openssh Approved by: so Sponsored by: The FreeBSD Foundation (cherry picked from commit 8a16d0831e70530b2fbd682e748bd051de35f192) (cherry picked from commit 34798cb576bbd2064ab8da372112482bf8e2a7e6) --- crypto/openssh/packet.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/crypto/openssh/packet.c b/crypto/openssh/packet.c index 2d1401e7c9f..d8fbfa28b80 100644 --- a/crypto/openssh/packet.c +++ b/crypto/openssh/packet.c @@ -1,4 +1,4 @@ -/* $OpenBSD: packet.c,v 1.313 2023/12/18 14:45:17 djm Exp $ */ +/* $OpenBSD: packet.c,v 1.318 2025/02/18 08:02:12 djm Exp $ */ /* * Author: Tatu Ylonen * Copyright (c) 1995 Tatu Ylonen , Espoo, Finland @@ -1774,6 +1774,14 @@ ssh_packet_read_poll_seqnr(struct ssh *ssh, u_char *typep, u_int32_t *seqnr_p) if ((r = sshpkt_get_string_direct(ssh, &d, &len)) != 0) return r; DBG(debug("Received SSH2_MSG_PING len %zu", len)); + if (!ssh->state->after_authentication) { + DBG(debug("Won't reply to PING in preauth")); + break; + } + if (ssh_packet_is_rekeying(ssh)) { + DBG(debug("Won't reply to PING during KEX")); + break; + } if ((r = sshpkt_start(ssh, SSH2_MSG_PONG)) != 0 || (r = sshpkt_put_string(ssh, d, len)) != 0 || (r = sshpkt_send(ssh)) != 0)