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)