From: Daniel Stenberg <daniel@haxx.se>
Date: Mon, 13 Aug 2018 08:35:52 +0000 (+0200)
Subject: Curl_ntlm_core_mk_nt_hash: return error on too long password
X-Git-Tag: curl-7_61_1~8
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=57d299a499155d4b327e341c6024e293b0418243;p=thirdparty%2Fcurl.git

Curl_ntlm_core_mk_nt_hash: return error on too long password

... since it would cause an integer overflow if longer than (max size_t
/ 2).

This is CVE-2018-14618

Bug: https://curl.haxx.se/docs/CVE-2018-14618.html
Closes #2756
Reported-by: Zhaoyang Wu
---

diff --git a/lib/curl_ntlm_core.c b/lib/curl_ntlm_core.c
index e27cab353c..922e85a926 100644
--- a/lib/curl_ntlm_core.c
+++ b/lib/curl_ntlm_core.c
@@ -557,8 +557,11 @@ CURLcode Curl_ntlm_core_mk_nt_hash(struct Curl_easy *data,
                                    unsigned char *ntbuffer /* 21 bytes */)
 {
   size_t len = strlen(password);
-  unsigned char *pw = len ? malloc(len * 2) : strdup("");
+  unsigned char *pw;
   CURLcode result;
+  if(len > SIZE_T_MAX/2) /* avoid integer overflow */
+    return CURLE_OUT_OF_MEMORY;
+  pw = len ? malloc(len * 2) : strdup("");
   if(!pw)
     return CURLE_OUT_OF_MEMORY;