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From ae2dc830fb37e9243dbdaf8b92e41df91f43b3f2 Mon Sep 17 00:00:00 2001
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From: Harry Sintonen <sintonen@iki.fi>
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Date: Fri, 7 May 2021 13:09:57 +0200
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Subject: [PATCH] telnet: check sscanf() for correct number of matches
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CVE-2021-22898
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Bug: https://curl.se/docs/CVE-2021-22898.html
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Upstream-commit: 39ce47f219b09c380b81f89fe54ac586c8db6bde
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Signed-off-by: Kamil Dudka <kdudka@redhat.com>
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---
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 lib/telnet.c | 2 +-
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 1 file changed, 1 insertion(+), 1 deletion(-)
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diff --git a/lib/telnet.c b/lib/telnet.c
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index 1fc5af1..ea6bc71 100644
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--- a/lib/telnet.c
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+++ b/lib/telnet.c
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@@ -967,7 +967,7 @@ static void suboption(struct connectdata *conn)
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         size_t tmplen = (strlen(v->data) + 1);
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         /* Add the variable only if it fits */
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         if(len + tmplen < (int)sizeof(temp)-6) {
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-          if(sscanf(v->data, "%127[^,],%127s", varname, varval)) {
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+          if(sscanf(v->data, "%127[^,],%127s", varname, varval) == 2) {
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             snprintf((char *)&temp[len], sizeof(temp) - len,
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                      "%c%s%c%s", CURL_NEW_ENV_VAR, varname,
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                      CURL_NEW_ENV_VALUE, varval);
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-- 
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2.31.1
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