CVE-2020-28016: Heap out-of-bounds write in parse_fix_phrase()

Based on Phil Pennock's commit 76a1ce77.
Modified by Qualys.

(cherry picked from commit f218fef171cbe9e61d10f15399aab8fa6956535b)

diff --git a/src/src/parse.c b/src/src/parse.c
index 32b42cd29771e81d50fd450bc9eab4af6c672195..086b010c3f2675f0ae7c5ffdefe0c577e45df857 100644 (file)
--- a/src/src/parse.c
+++ b/src/src/parse.c
@@ -979,12 +979,12 @@ if (i < len)
 
 /* No non-printers; use the RFC 822 quoting rules */
 
-if (!len)
+if (len <= 0 || len >= INT_MAX/4)
   {
-  return string_copy_taint(US"", is_tainted(phrase));
+  return string_copy_taint(CUS"", is_tainted(phrase));
   }
 
-buffer = store_get(len*4, is_tainted(phrase));
+buffer = store_get((len+1)*4, is_tainted(phrase));
 
 s = phrase;
 end = s + len;