Project: liblouis (liblouis/liblouis), language: c++
Vulnerability instance: liblouis.cve-2018-11685
Sanitizer: address

================= Bug Report (1/1) ==================
## Source: GitHub Issue
## URL: https://github.com/liblouis/liblouis/issues/593
## Description:
Issue: liblouis/liblouis#593
Title: ASAn stack-based buffer overflow in compileTranslationTable.c in 3038 in compileHyphenation
State: closed
Created by: fgeek
Created at: 2018-06-02 11:14:59+00:00
Labels: memory error

Issue Body:
[9da60dd470ed9a8e2dddc7fdecd14f5c12b5326d.ctb.zip](https://github.com/liblouis/liblouis/files/2064927/9da60dd470ed9a8e2dddc7fdecd14f5c12b5326d.ctb.zip)
Tested commit: b381efd3248902ed2f9a797a46f79dfa0690a9c4
Credit: Henri Salo
Tools: [american fuzzy lop](http://lcamtuf.coredump.cx/afl/) 2.52b, [afl-utils](https://github.com/rc0r/afl-utils)
Thanks to Kapsi internet-käyttäjät ry for providing valuable fuzzing resources.
```
./lou_checktable 9da60dd470ed9a8e2dddc7fdecd14f5c12b5326d.ctb
=================================================================
==7998==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7ffe38b6b4a0 at pc 0x7f3e741d3049 bp 0x7ffe38b6aa30 sp 0x7ffe38b6aa28
WRITE of size 1 at 0x7ffe38b6b4a0 thread T0
    #0 0x7f3e741d3048 in compileHyphenation /home/hsalo/src/liblouis/liblouis/compileTranslationTable.c:3038
    #1 0x7f3e741d3048 in compileRule /home/hsalo/src/liblouis/liblouis/compileTranslationTable.c:3184
    #2 0x7f3e741df4ca in compileFile /home/hsalo/src/liblouis/liblouis/compileTranslationTable.c:4522
    #3 0x7f3e741e0707 in compileTranslationTable /home/hsalo/src/liblouis/liblouis/compileTranslationTable.c:4627
    #4 0x7f3e741e0707 in lou_getTable /home/hsalo/src/liblouis/liblouis/compileTranslationTable.c:4712
    #5 0x5589513a7f33 in main /home/hsalo/src/liblouis/tools/lou_checktable.c:112
    #6 0x7f3e73df62e0 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x202e0)
    #7 0x5589513a8199 in _start (/home/hsalo/builds/liblouis/b381efd3248902ed2f9a797a46f79dfa0690a9c4/bin/lou_checktable+0x2199)

Address 0x7ffe38b6b4a0 is located in stack of thread T0 at offset 2528 in frame
    #0 0x7f3e741c0b9f in compileRule /home/hsalo/src/liblouis/liblouis/compileTranslationTable.c:3156

  This frame has 17 object(s):
    [32, 34) 'c'
    [96, 98) 'c'
    [160, 164) 'lastToken'
    [224, 228) 'after'
    [288, 292) 'before'
    [352, 356) 'holdOffset'
    [416, 432) 'dict'
    [480, 2528) 'includeThis' <== Memory access at offset 2528 overflows this variable
    [2560, 6658) 'token'
    [6720, 10818) 'ruleChars'
    [10880, 14978) 'ruleDots'
    [15040, 19138) 'name'
    [19200, 23298) 'ruleChars'
    [23360, 27458) 'ruleDots'
    [27520, 31618) 'upperDots'
    [31680, 35778) 'lowerDots'
    [35840, 39984) 'nested'
HINT: this may be a false positive if your program uses some custom stack unwind mechanism or swapcontext
      (longjmp and C++ exceptions *are* supported)
SUMMARY: AddressSanitizer: stack-buffer-overflow /home/hsalo/src/liblouis/liblouis/compileTranslationTable.c:3038 in compileHyphenation
Shadow bytes around the buggy address:
  0x100047165640: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x100047165650: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x100047165660: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x100047165670: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x100047165680: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>0x100047165690: 00 00 00 00[f2]f2 f2 f2 00 00 00 00 00 00 00 00
  0x1000471656a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x1000471656b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x1000471656c0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x1000471656d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x1000471656e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Shadow byte legend (one shadow byte represents 8 application bytes):
  Addressable:           00
  Partially addressable: 01 02 03 04 05 06 07
  Heap left redzone:       fa
  Heap right redzone:      fb
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  Stack partial redzone:   f4
  Stack after return:      f5
  Stack use after scope:   f8
  Global redzone:          f9
  Global init order:       f6
  Poisoned by user:        f7
  Container overflow:      fc
  Array cookie:            ac
  Intra object redzone:    bb
  ASan internal:           fe
  Left alloca redzone:     ca
  Right alloca redzone:    cb
==7998==ABORTING
```


Comments:
Comment by fgeek on 2018-06-02 19:36:57+00:00:
After 230 million AFL fuzzer executions and ~1922 crashes found I can only detect these three open issues currently when using lou_checktable binary. I can also check other binaries later.

Thank you again for your work to create good open-source software. Much appreciated.

---

Comment by sthibaul on 2018-06-03 00:48:00+00:00:
Well, it's good to check lou_checktable, but attackers usually control the text input, not the braille table, so it'd be more useful to try to run e.g.

lou_translate en-us-g2.ctb < fuzzy-input.txt

and even doing it for all .tbl, .ctb, and .utb files

---

Comment by fgeek on 2018-06-03 07:41:33+00:00:
@sthibaul I can do that next. Thanks

---

Comment by abergmann on 2018-06-04 14:05:04+00:00:
[CVE-2018-11685](https://nvd.nist.gov/vuln/detail/CVE-2018-11685) was assigned to this issue.

Attachments:
https://github.com/liblouis/liblouis/files/2064927/9da60dd470ed9a8e2dddc7fdecd14f5c12b5326d.ctb.zip

Commit References:
b381efd3248902ed2f9a797a46f79dfa0690a9c4
9da60dd470ed9a8e2dddc7fdecd14f5c12b5326d

Build script:
#!/bin/bash
# Default build script template for C/C++ projects
set -eu

# Define configuration options
CONFIG_OPTS="--disable-shared"
CMAKE_OPTS="-DCMAKE_BUILD_TYPE=Debug"
MAKE_OPTS="-j$(nproc)"
BUILD_DIR="build"

# 1. Run build preparation scripts if they exist
for prep_script in buildconf autogen.sh bootstrap; do
  if [ -x "$prep_script" ]; then
    echo "Running $prep_script..."
    ./$prep_script
    break
  elif [ -f "$prep_script" ]; then
    echo "Found $prep_script but it's not executable, setting permissions..."
    chmod +x $prep_script
    ./$prep_script
    break
  fi
done

# 2. Handle different build systems
if [ -f "configure" ]; then
  echo "Found configure script, running with options: $CONFIG_OPTS"
  ./configure $CONFIG_OPTS

  echo "Building with make $MAKE_OPTS"
  make $MAKE_OPTS
elif [ -f "CMakeLists.txt" ]; then
  echo "Found CMakeLists.txt, using CMake build system"
  mkdir -p $BUILD_DIR
  cd $BUILD_DIR
  cmake $CMAKE_OPTS ..
  make $MAKE_OPTS
elif [ -f "Makefile" ] || [ -f "makefile" ]; then
  echo "Found Makefile, building with make $MAKE_OPTS"
  make $MAKE_OPTS
elif [ -f "meson.build" ]; then
  echo "Found meson.build, using Meson build system"
  mkdir -p $BUILD_DIR
  meson setup $BUILD_DIR .
  cd $BUILD_DIR
  ninja
elif [ -f "GNUmakefile" ]; then
  echo "Found GNUmakefile, building with make $MAKE_OPTS"
  make $MAKE_OPTS
elif [ -d ".git" ] && [ -f "Makefile.am" ]; then
  echo "Found Makefile.am, running autoreconf"
  autoreconf -i
  ./configure $CONFIG_OPTS
  make $MAKE_OPTS
else
  echo "WARNING: No recognized build system found!"
  echo "Trying generic approach:"
  
  # Try to detect common source patterns and compile them
  if ls *.c >/dev/null 2>&1 || ls *.cpp >/dev/null 2>&1 || ls *.cc >/dev/null 2>&1; then
    echo "Found C/C++ source files, attempting direct compilation"
    if ls *.cpp >/dev/null 2>&1 || ls *.cc >/dev/null 2>&1; then
      CXX=${CXX:-g++}
      echo "Compiling C++ sources with $CXX"
      $CXX -g -O1 -fsanitize=address -fno-omit-frame-pointer -o main *.cpp *.cc 2>/dev/null || true
    elif ls *.c >/dev/null 2>&1; then
      CC=${CC:-gcc}
      echo "Compiling C sources with $CC"
      $CC -g -O1 -fsanitize=address -fno-omit-frame-pointer -o main *.c 2>/dev/null || true
    fi
  fi
fi

Dockerfile:
FROM hwiwonlee/secb.base:latest
RUN apt-get update && apt-get install -y make autoconf automake libtool pkg-config zlib1g-dev libpci-dev
RUN git clone https://github.com/liblouis/liblouis liblouis
RUN git -C liblouis checkout 0dee1fcc102678e8a57f59ba53f0a9784b93b4ae
WORKDIR $SRC/liblouis
COPY build.sh $SRC/

Additional files: