1*eb8dc403SDave Cobbleyp7zip: Fix CVE-2017-17969 2*eb8dc403SDave Cobbley 3*eb8dc403SDave Cobbley[No upstream tracking] -- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=888297 4*eb8dc403SDave Cobbley 5*eb8dc403SDave CobbleyHeap-based buffer overflow in 7zip 6*eb8dc403SDave Cobbley 7*eb8dc403SDave CobbleyCompress/ShrinkDecoder.cpp: Heap-based buffer overflow 8*eb8dc403SDave Cobbleyin the NCompress::NShrink::CDecoder::CodeReal method 9*eb8dc403SDave Cobbleyin 7-Zip before 18.00 and p7zip allows remote attackers 10*eb8dc403SDave Cobbleyto cause a denial of service (out-of-bounds write) 11*eb8dc403SDave Cobbleyor potentially execute arbitrary code via a crafted ZIP archive. 12*eb8dc403SDave Cobbley 13*eb8dc403SDave CobbleyUpstream-Status: Backport [https://sourceforge.net/p/p7zip/bugs/_discuss/thread/0920f369/8316/attachment/CVE-2017-17969.patch] 14*eb8dc403SDave CobbleyCVE: CVE-2017-17969 15*eb8dc403SDave CobbleySigned-off-by: Radovan Scasny <radovan.scasny@siemens.com> 16*eb8dc403SDave Cobbley 17*eb8dc403SDave Cobbley--- a/CPP/7zip/Compress/ShrinkDecoder.cpp 18*eb8dc403SDave Cobbley+++ b/CPP/7zip/Compress/ShrinkDecoder.cpp 19*eb8dc403SDave Cobbley@@ -121,7 +121,12 @@ HRESULT CDecoder::CodeReal(ISequentialInStream *inStream, ISequentialOutStream * 20*eb8dc403SDave Cobbley { 21*eb8dc403SDave Cobbley _stack[i++] = _suffixes[cur]; 22*eb8dc403SDave Cobbley cur = _parents[cur]; 23*eb8dc403SDave Cobbley+ if (cur >= kNumItems || i >= kNumItems) 24*eb8dc403SDave Cobbley+ break; 25*eb8dc403SDave Cobbley } 26*eb8dc403SDave Cobbley+ 27*eb8dc403SDave Cobbley+ if (cur >= kNumItems || i >= kNumItems) 28*eb8dc403SDave Cobbley+ break; 29*eb8dc403SDave Cobbley 30*eb8dc403SDave Cobbley _stack[i++] = (Byte)cur; 31*eb8dc403SDave Cobbley lastChar2 = (Byte)cur; 32