Fix from http://antinode.info/ftp/info-zip/unzip60/zipinfo.c
diff --git a/zipinfo.c b/zipinfo.c
index a92bca9..8f8e729 100644
--- a/zipinfo.c
+++ b/zipinfo.c
@@ -1,5 +1,5 @@
/*
- Copyright (c) 1990-2009 Info-ZIP. All rights reserved.
+ Copyright (c) 1990-2016 Info-ZIP. All rights reserved.
See the accompanying file LICENSE, version 2009-Jan-02 or later
(the contents of which are also included in unzip.h) for terms of use.
@@ -1921,7 +1921,18 @@ static int zi_short(__G) /* return PK-type error code */
ush dnum=(ush)((G.crec.general_purpose_bit_flag>>1) & 3);
methbuf[3] = dtype[dnum];
} else if (methnum >= NUM_METHODS) { /* unknown */
- sprintf(&methbuf[1], "%03u", G.crec.compression_method);
+ /* 2016-12-05 SMS.
+ * https://launchpad.net/bugs/1643750 CVE-2016-9844.
+ * Unexpectedly large compression methods overflow
+ * &methbuf[]. Use the old, three-digit decimal format
+ * for values which fit. Otherwise, sacrifice the "u",
+ * and use four-digit hexadecimal.
+ */
+ if (G.crec.compression_method <= 999) {
+ sprintf( &methbuf[ 1], "%03u", G.crec.compression_method);
+ } else {
+ sprintf( &methbuf[ 0], "%04X", G.crec.compression_method);
+ }
}
for (k = 0; k < 15; ++k)