From ff18fec24b119579df26fd2ebb8bb012cde102ce Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Dan=20=C4=8Cerm=C3=A1k?= Date: Fri, 6 Oct 2017 23:09:08 +0200 Subject: [PATCH] Fix for CVE-2017-14860 A heap buffer overflow could occur in memcpy when icc.size_ is larger than data.size_ - pad, as then memcpy would read out of bounds of data. This commit adds a sanity check to iccLength (= icc.size_): if it is larger than data.size_ - pad (i.e. an overflow would be caused) an exception is thrown. This fixes #71. --- src/jp2image.cpp | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/src/jp2image.cpp b/src/jp2image.cpp index 747145cf91..748d39b58a 100644 --- a/src/jp2image.cpp +++ b/src/jp2image.cpp @@ -269,10 +269,15 @@ namespace Exiv2 std::cout << "Exiv2::Jp2Image::readMetadata: " << "Color data found" << std::endl; #endif - long pad = 3 ; // 3 padding bytes 2 0 0 + const long pad = 3 ; // 3 padding bytes 2 0 0 DataBuf data(subBox.length+8); io_->read(data.pData_,data.size_); - long iccLength = getULong(data.pData_+pad, bigEndian); + const long iccLength = getULong(data.pData_+pad, bigEndian); + // subtracting pad from data.size_ is safe: + // size_ is at least 8 and pad = 3 + if (iccLength > data.size_ - pad) { + throw Error(58); + } DataBuf icc(iccLength); ::memcpy(icc.pData_,data.pData_+pad,icc.size_); #ifdef DEBUG