Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=744 We have identified the following crash due to an out-of-bounds read in Foxit PDF Reader (version 1.0.1.0925 for Linux 64-bit), when started with a specially crafted PDF file in the following way: $ MALLOC_CHECK_=3 DISPLAY=:1 FoxitReader /path/to/poc/file.pdf The MALLOC_CHECK_=3 environment variable is used to enforce strict checks in the libc memory allocator, while DISPLAY=:1 is set due to the fact that we are testing the application with a virtual X server (Xvfb), but the issue should be equally reproducible with the program started with standard display settings, too. An example excerpt from the crash log is as follows: --- cut --- Program received signal SIGSEGV, Segmentation fault. 0x00000000007fb462 in CPDF_DIBSource::TranslateScanline24bpp(unsigned char*, unsigned char const*) const () (gdb) where #0 0x00000000007fb462 in CPDF_DIBSource::TranslateScanline24bpp(unsigned char*, unsigned char const*) const () #1 0x00000000007fbd6c in CPDF_DIBSource::GetScanline(int) const () #2 0x000000000084b849 in CFX_DIBSource::Clone(FX_RECT const*) const () #3 0x00000000007f2e71 in CPDF_ImageCache::ContinueGetCachedBitmap() () #4 0x00000000007f2f9e in CPDF_ImageCache::StartGetCachedBitmap(CPDF_Dictionary*, CPDF_Dictionary*, int, unsigned int, int, CPDF_RenderStatus*, int, int) () #5 0x00000000007f3ba0 in CPDF_PageRenderCache::StartGetCachedBitmap(CPDF_Stream*, int, unsigned int, int, CPDF_RenderStatus*, int, int) () #6 0x00000000007fb00d in CPDF_ProgressiveImageLoaderHandle::Start(CPDF_ImageLoader*, CPDF_ImageObject const*, CPDF_PageRenderCache*, int, unsigned int, int, CPDF_RenderStatus*, int, int) () #7 0x00000000007fb13b in CPDF_ImageLoader::StartLoadImage(CPDF_ImageObject const*, CPDF_PageRenderCache*, void*&, int, unsigned int, int, CPDF_RenderStatus*, int, int) () #8 0x00000000007f42ff in CPDF_ImageRenderer::StartLoadDIBSource() () #9 0x00000000007f6782 in CPDF_ImageRenderer::Start(CPDF_RenderStatus*, CPDF_PageObject const*, CFX_Matrix const*, int, int) () #10 0x00000000007f1689 in CPDF_RenderStatus::ContinueSingleObject(CPDF_PageObject const*, CFX_Matrix const*, IFX_Pause*) () #11 0x00000000007f237a in CPDF_ProgressiveRenderer::Continue(IFX_Pause*) () #12 0x000000000061d75d in CPDFViewerPageEx::Rendering(CFX_DIBitmap*, int, int, int, int, int, CPDF_RenderOptions*) () #13 0x000000000061d9cb in CPDFViewerPageEx::DrawPageContent(CFX_DIBitmap*, CFX_ViewRect&) () #14 0x000000000061da6a in CPDFViewerEx::DrawPages(CFX_DIBitmap*) () #15 0x000000000061daa8 in CPDFViewerEx::Paint(CFX_DIBitmap*) () #16 0x000000000061daf1 in CPDFViewerEx::ContinueRendering() () #17 0x000000000061de17 in CPDFViewerEx::GetRenderData(int) () #18 0x000000000044b274 in CPDF_TVPreview::paintEvent (this=0x191fca0) at ../../Readerlite/ReaderLite/src/preview.cpp:1305 #19 0x00007ffff74c2302 in QWidget::event(QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #20 0x00007ffff7486c8c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #21 0x00007ffff748be56 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #22 0x00007ffff6340c2d in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #23 0x00007ffff74bcbea in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #24 0x00007ffff74bd5bc in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #25 0x00007ffff74bc786 in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #26 0x00007ffff74bd5bc in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #27 0x00007ffff74bd434 in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #28 0x00007ffff74bc786 in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #29 0x00007ffff74bd5bc in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #30 0x00007ffff74bc786 in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #31 0x00007ffff74bd5bc in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #32 0x00007ffff74bd434 in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #33 0x00007ffff74bd434 in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () ---Type to continue, or q to quit--- from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #34 0x00007ffff74bd434 in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #35 0x00007ffff74bc786 in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #36 0x00007ffff74bd5bc in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #37 0x00007ffff74bd434 in QWidgetPrivate::paintSiblingsRecursive(QPaintDevice*, QList const&, int, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #38 0x00007ffff74bc786 in QWidgetPrivate::drawWidget(QPaintDevice*, QRegion const&, QPoint const&, int, QPainter*, QWidgetBackingStore*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #39 0x00007ffff7493233 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #40 0x00007ffff7493941 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #41 0x00007ffff74e0973 in ?? () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #42 0x00007ffff7486c8c in QApplicationPrivate::notify_helper(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #43 0x00007ffff748be56 in QApplication::notify(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Widgets.so.5 #44 0x00007ffff6340c2d in QCoreApplication::notifyInternal(QObject*, QEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #45 0x00007ffff6860ea6 in QGuiApplicationPrivate::processExposeEvent(QWindowSystemInterfacePrivate::ExposeEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5 #46 0x00007ffff6861995 in QGuiApplicationPrivate::processWindowSystemEvent(QWindowSystemInterfacePrivate::WindowSystemEvent*) () from /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5 #47 0x00007ffff684a858 in QWindowSystemInterface::sendWindowSystemEvents(QFlags) () from /usr/lib/x86_64-linux-gnu/libQt5Gui.so.5 #48 0x00007fffecc415b0 in ?? () from /usr/lib/x86_64-linux-gnu/qt5/plugins/platforms/libqxcb.so #49 0x00007ffff4a79e04 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0 #50 0x00007ffff4a7a048 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0 #51 0x00007ffff4a7a0ec in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0 #52 0x00007ffff638d98c in QEventDispatcherGlib::processEvents(QFlags) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #53 0x00007ffff633f96b in QEventLoop::exec(QFlags) () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #54 0x00007ffff63460e1 in QCoreApplication::exec() () from /usr/lib/x86_64-linux-gnu/libQt5Core.so.5 #55 0x0000000000439e25 in main (argc=2, argv=0x7fffffffe288) at ../../Readerlite/ReaderLite/src/main.cpp:310 (gdb) x/10i $rip => 0x7fb462 <_ZNK14CPDF_DIBSource22TranslateScanline24bppEPhPKh+188>: mov 0x2(%rbp),%dl 0x7fb465 <_ZNK14CPDF_DIBSource22TranslateScanline24bppEPhPKh+191>: add $0x3,%r13 0x7fb469 <_ZNK14CPDF_DIBSource22TranslateScanline24bppEPhPKh+195>: add $0x3,%rbp 0x7fb46d <_ZNK14CPDF_DIBSource22TranslateScanline24bppEPhPKh+199>: inc %eax 0x7fb46f <_ZNK14CPDF_DIBSource22TranslateScanline24bppEPhPKh+201>: mov %dl,-0x3(%r13) 0x7fb473 <_ZNK14CPDF_DIBSource22TranslateScanline24bppEPhPKh+205>: mov -0x2(%rbp),%dl 0x7fb476 <_ZNK14CPDF_DIBSource22TranslateScanline24bppEPhPKh+208>: mov %dl,-0x2(%r13) 0x7fb47a <_ZNK14CPDF_DIBSource22TranslateScanline24bppEPhPKh+212>: mov -0x3(%rbp),%dl 0x7fb47d <_ZNK14CPDF_DIBSource22TranslateScanline24bppEPhPKh+215>: mov %dl,-0x1(%r13) 0x7fb481 <_ZNK14CPDF_DIBSource22TranslateScanline24bppEPhPKh+219>: jmp 0x7fb459 <_ZNK14CPDF_DIBSource22TranslateScanline24bppEPhPKh+179> (gdb) info reg $rbp rbp 0x1a30fff 0x1a30fff --- cut --- Attached is a proof of concept PDF file. Proof of Concept: https://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/39941.zip