From 39ce47f219b09c380b81f89fe54ac586c8db6bde Mon Sep 17 00:00:00 2001 From: Harry Sintonen Date: Fri, 7 May 2021 13:09:57 +0200 Subject: [PATCH] telnet: check sscanf() for correct number of matches CVE-2021-22898 Bug: https://curl.se/docs/CVE-2021-22898.html --- lib/telnet.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/lib/telnet.c b/lib/telnet.c index 26e0658ba9cc..fdd137fb0c04 100644 --- a/lib/telnet.c +++ b/lib/telnet.c @@ -922,7 +922,7 @@ static void suboption(struct Curl_easy *data) size_t tmplen = (strlen(v->data) + 1); /* Add the variable only if it fits */ if(len + tmplen < (int)sizeof(temp)-6) { - if(sscanf(v->data, "%127[^,],%127s", varname, varval)) { + if(sscanf(v->data, "%127[^,],%127s", varname, varval) == 2) { msnprintf((char *)&temp[len], sizeof(temp) - len, "%c%s%c%s", CURL_NEW_ENV_VAR, varname, CURL_NEW_ENV_VALUE, varval);