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Fix CVE-2026-3497 #244

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12 changes: 6 additions & 6 deletions gsi_openssh/source/kexgssc.c
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Original file line number Diff line number Diff line change
Expand Up @@ -125,7 +125,7 @@ kexgss_final(struct ssh *ssh)

/* Verify that the hash matches the MIC we just got. */
if (GSS_ERROR(ssh_gssapi_checkmic(gss, &gss->buf, &gss->msg_tok)))
sshpkt_disconnect(ssh, "Hash's MIC didn't verify");
ssh_packet_disconnect(ssh, "Hash's MIC didn't verify");

gss_release_buffer(&gss->minor, &gss->msg_tok);

Expand Down Expand Up @@ -348,10 +348,10 @@ input_kexgss_complete(int type,
fatal("Failed to read token: %s", ssh_err(r));
/* If we're already complete - protocol error */
if (gss->major == GSS_S_COMPLETE)
sshpkt_disconnect(ssh, "Protocol error: received token when complete");
ssh_packet_disconnect(ssh, "Protocol error: received token when complete");
} else {
if (gss->major != GSS_S_COMPLETE)
sshpkt_disconnect(ssh, "Protocol error: did not receive final token");
ssh_packet_disconnect(ssh, "Protocol error: did not receive final token");
}
if ((r = sshpkt_get_end(ssh)) != 0)
fatal("Expecting end of packet.");
Expand Down Expand Up @@ -487,7 +487,7 @@ kexgssgex_final(struct ssh *ssh)

/* Verify that the hash matches the MIC we just got. */
if (GSS_ERROR(ssh_gssapi_checkmic(gss, &gss->buf, &gss->msg_tok)))
sshpkt_disconnect(ssh, "Hash's MIC didn't verify");
ssh_packet_disconnect(ssh, "Hash's MIC didn't verify");

gss_release_buffer(&gss->minor, &gss->msg_tok);

Expand Down Expand Up @@ -688,10 +688,10 @@ input_kexgssgex_complete(int type,
fatal("Failed to read token: %s", ssh_err(r));
/* If we're already complete - protocol error */
if (gss->major == GSS_S_COMPLETE)
sshpkt_disconnect(ssh, "Protocol error: received token when complete");
ssh_packet_disconnect(ssh, "Protocol error: received token when complete");
} else {
if (gss->major != GSS_S_COMPLETE)
sshpkt_disconnect(ssh, "Protocol error: did not receive final token");
ssh_packet_disconnect(ssh, "Protocol error: did not receive final token");
}
if ((r = sshpkt_get_end(ssh)) != 0)
fatal("Expecting end of packet.");
Expand Down
19 changes: 11 additions & 8 deletions gsi_openssh/source/kexgsss.c
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Original file line number Diff line number Diff line change
Expand Up @@ -132,7 +132,7 @@ kexgss_final(struct ssh *ssh,
{
struct kex *kex = ssh->kex;
Gssctxt *gss = kex->gss;
gss_buffer_desc msg_tok;
gss_buffer_desc msg_tok = GSS_C_EMPTY_BUFFER;;
u_char hash[SSH_DIGEST_MAX_LENGTH];
size_t hashlen;
struct sshbuf *shared_secret = NULL;
Expand Down Expand Up @@ -217,7 +217,8 @@ input_kexgss_init(int type,
Gssctxt *gss = kex->gss;
struct sshbuf *empty;
struct sshbuf *client_pubkey = NULL;
gss_buffer_desc recv_tok, send_tok = GSS_C_EMPTY_BUFFER;
gss_buffer_desc recv_tok = GSS_C_EMPTY_BUFFER;
gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
OM_uint32 ret_flags = 0;
int r;

Expand Down Expand Up @@ -293,7 +294,8 @@ input_kexgss_continue(int type,
struct ssh *ssh)
{
Gssctxt *gss = ssh->kex->gss;
gss_buffer_desc recv_tok, send_tok = GSS_C_EMPTY_BUFFER;
gss_buffer_desc recv_tok = GSS_C_EMPTY_BUFFER;
gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
OM_uint32 ret_flags = 0;
int r;

Expand Down Expand Up @@ -384,7 +386,7 @@ kexgssgex_final(struct ssh *ssh,
{
struct kex *kex = ssh->kex;
Gssctxt *gss = kex->gss;
gss_buffer_desc msg_tok;
gss_buffer_desc msg_tok = GSS_C_EMPTY_BUFFER;;
u_char hash[SSH_DIGEST_MAX_LENGTH];
size_t hashlen;
const BIGNUM *pub_key, *dh_p, *dh_g;
Expand Down Expand Up @@ -526,8 +528,7 @@ input_kexgssgex_groupreq(int type,

kex->dh = mm_choose_dh(min, nbits, max);
if (kex->dh == NULL) {
sshpkt_disconnect(ssh, "Protocol error: no matching group found");
fatal("Protocol error: no matching group found");
ssh_packet_disconnect(ssh, "Protocol error: no matching group found");
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@fscheiner fscheiner Apr 12, 2026

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@msalle : Here I wonder if that is enough, as the original code did end - I guess the key exchange - with fatal() at this point. But the change by Red Hat has it that way.

}

DH_get0_pqg(kex->dh, &dh_p, NULL, &dh_g);
Expand Down Expand Up @@ -560,7 +561,8 @@ input_kexgssgex_init(int type,
struct ssh *ssh)
{
Gssctxt *gss = ssh->kex->gss;
gss_buffer_desc recv_tok, send_tok = GSS_C_EMPTY_BUFFER;
gss_buffer_desc recv_tok = GSS_C_EMPTY_BUFFER;
gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
OM_uint32 ret_flags = 0;
int r;

Expand All @@ -587,7 +589,8 @@ input_kexgssgex_continue(int type,
struct ssh *ssh)
{
Gssctxt *gss = ssh->kex->gss;
gss_buffer_desc recv_tok, send_tok = GSS_C_EMPTY_BUFFER;
gss_buffer_desc recv_tok = GSS_C_EMPTY_BUFFER;
gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
OM_uint32 ret_flags = 0;
int r;

Expand Down
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