| p7zip: Fix CVE-2017-17969 |
| |
| [No upstream tracking] -- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=888297 |
| |
| Heap-based buffer overflow in 7zip |
| |
| Compress/ShrinkDecoder.cpp: Heap-based buffer overflow |
| in the NCompress::NShrink::CDecoder::CodeReal method |
| in 7-Zip before 18.00 and p7zip allows remote attackers |
| to cause a denial of service (out-of-bounds write) |
| or potentially execute arbitrary code via a crafted ZIP archive. |
| |
| Upstream-Status: Backport [https://sourceforge.net/p/p7zip/bugs/_discuss/thread/0920f369/8316/attachment/CVE-2017-17969.patch] |
| CVE: CVE-2017-17969 |
| Signed-off-by: Radovan Scasny <radovan.scasny@siemens.com> |
| |
| --- a/CPP/7zip/Compress/ShrinkDecoder.cpp |
| +++ b/CPP/7zip/Compress/ShrinkDecoder.cpp |
| @@ -121,7 +121,12 @@ HRESULT CDecoder::CodeReal(ISequentialInStream *inStream, ISequentialOutStream * |
| { |
| _stack[i++] = _suffixes[cur]; |
| cur = _parents[cur]; |
| + if (cur >= kNumItems || i >= kNumItems) |
| + break; |
| } |
| + |
| + if (cur >= kNumItems || i >= kNumItems) |
| + break; |
| |
| _stack[i++] = (Byte)cur; |
| lastChar2 = (Byte)cur; |