| Brad Bishop | 316dfdd | 2018-06-25 12:45:53 -0400 | [diff] [blame] | 1 | p7zip: Fix CVE-2017-17969 |
| 2 | |
| 3 | [No upstream tracking] -- https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=888297 |
| 4 | |
| 5 | Heap-based buffer overflow in 7zip |
| 6 | |
| 7 | Compress/ShrinkDecoder.cpp: Heap-based buffer overflow |
| 8 | in the NCompress::NShrink::CDecoder::CodeReal method |
| 9 | in 7-Zip before 18.00 and p7zip allows remote attackers |
| 10 | to cause a denial of service (out-of-bounds write) |
| 11 | or potentially execute arbitrary code via a crafted ZIP archive. |
| 12 | |
| 13 | Upstream-Status: Backport [https://sourceforge.net/p/p7zip/bugs/_discuss/thread/0920f369/8316/attachment/CVE-2017-17969.patch] |
| 14 | CVE: CVE-2017-17969 |
| 15 | Signed-off-by: Radovan Scasny <radovan.scasny@siemens.com> |
| 16 | |
| 17 | --- a/CPP/7zip/Compress/ShrinkDecoder.cpp |
| 18 | +++ b/CPP/7zip/Compress/ShrinkDecoder.cpp |
| 19 | @@ -121,7 +121,12 @@ HRESULT CDecoder::CodeReal(ISequentialInStream *inStream, ISequentialOutStream * |
| 20 | { |
| 21 | _stack[i++] = _suffixes[cur]; |
| 22 | cur = _parents[cur]; |
| 23 | + if (cur >= kNumItems || i >= kNumItems) |
| 24 | + break; |
| 25 | } |
| 26 | + |
| 27 | + if (cur >= kNumItems || i >= kNumItems) |
| 28 | + break; |
| 29 | |
| 30 | _stack[i++] = (Byte)cur; |
| 31 | lastChar2 = (Byte)cur; |