[CVE ID] CVE-2025-63927

[PRODUCT INFORMATION]

[AFFECTED VERSION]

[VULNERABILITY TYPE]

heap-use-after-free

[DESCRIPTION]

A heap-use-after-free vulnerability exists in airpig2011 IEC104 thru Commit be6d841 (2019-07-08). During multi-threaded client execution, the function Iec10x_Scheduled can access memory that has already been freed, potentially causing program crashes or undefined behavior. This may be exploited to trigger a denial-of-service or memory corruption.

[REPRODUCTION STEPS]

  1. Environment Setup: Compile `iec104_monitor` with AddressSanitizer (ASan) enabled to capture memory error details.
  2. Launch Command: Run the program in client mode with high-concurrency parameters: ./iec104_monitor -m client -n 100 -p 10000 (-m: client mode; -n: 100 threads to trigger race conditions; -p: port 10000)
  3. Trigger Condition: During continuous execution, concurrent threads interact with the priority queue in three key steps: Thread T7 first allocates a 53-byte memory block via `IEC10X_Enqueue` (in `Iec10x.c:72`); Thread T74 then frees this block via `IEC10X_Prio_ClearQueue` (in `PRIO_QUEUE_Iec10x.c:135`); subsequently, Thread T96 invokes `Iec10x_Scheduled` (in `Iec10x.c:136`) and attempts to read 2 bytes from the already freed memory region. AddressSanitizer will detect a "heap-use-after-free" error at `Iec10x.c:136`, leading to immediate program abortion.

[ASAN REPORT]

=================================================================
==7243==ERROR: AddressSanitizer: heap-use-after-free on address 0x606000000020 at pc 0x0000004d08d1 bp 0x7a40f171ce30 sp 0x7a40f171ce28
READ of size 2 at 0x606000000020 thread T96
    #0 0x4d08d0 in Iec10x_Scheduled /IEC104-master/test/..//IEC10X/Iec10x.c:136:9
    #1 0x4d1495 in Iec104_Task /IEC104-master/test/main.c:65:9
    #2 0x7a4125529183 in start_thread (/lib/x86_64-linux-gnu/libpthread.so.0+0x8183)
    #3 0x7a412492e03c in clone (/lib/x86_64-linux-gnu/libc.so.6+0xfe03c)

0x606000000020 is located 0 bytes inside of 53-byte region [0x606000000020,0x606000000055)
freed by thread T74 here:
    #0 0x492eed in free /tmp/final/llvm.src/projects/compiler-rt/lib/asan/asan_malloc_linux.cc:123:3
    #1 0x4cf134 in IEC10X_Prio_ClearQueue /IEC104-master/test/..//IEC10X/PRIO_QUEUE_Iec10x.c:135:9

previously allocated by thread T7 here:
    #0 0x49316d in malloc /tmp/final/llvm.src/projects/compiler-rt/lib/asan/asan_malloc_linux.cc:145:3
    #1 0x4cfd9a in IEC10X_Enqueue /IEC104-master/test/..//IEC10X/Iec10x.c:72:34

Thread T96 created by T94 here:
    #0 0x47d8fa in pthread_create /tmp/final/llvm.src/projects/compiler-rt/lib/asan/asan_interceptors.cc:209:3
    #1 0x4d237d in Iec104_Client /IEC104-master/test/main.c:168:9
    #2 0x7a4125529183 in start_thread (/lib/x86_64-linux-gnu/libpthread.so.0+0x8183)

Thread T94 created by T0 here:
    #0 0x47d8fa in pthread_create /tmp/final/llvm.src/projects/compiler-rt/lib/asan/asan_interceptors.cc:209:3
    #1 0x4d34bb in main /IEC104-master/test/main.c:311:11
    #2 0x7a4124851f44 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21f44)

Thread T74 created by T67 here:
    #0 0x47d8fa in pthread_create /tmp/final/llvm.src/projects/compiler-rt/lib/asan/asan_interceptors.cc:209:3
    #1 0x4d237d in Iec104_Client /IEC104-master/test/main.c:168:9
    #2 0x7a4125529183 in start_thread (/lib/x86_64-linux-gnu/libpthread.so.0+0x8183)

Thread T67 created by T0 here:
    #0 0x47d8fa in pthread_create /tmp/final/llvm.src/projects/compiler-rt/lib/asan/asan_interceptors.cc:209:3
    #1 0x4d34bb in main /IEC104-master/test/main.c:311:11
    #2 0x7a4124851f44 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21f44)

Thread T7 created by T4 here:
    #0 0x47d8fa in pthread_create /tmp/final/llvm.src/projects/compiler-rt/lib/asan/asan_interceptors.cc:209:3
    #1 0x4d237d in Iec104_Client /IEC104-master/test/main.c:168:9
    #2 0x7a4125529183 in start_thread (/lib/x86_64-linux-gnu/libpthread.so.0+0x8183)

Thread T4 created by T0 here:
    #0 0x47d8fa in pthread_create /tmp/final/llvm.src/projects/compiler-rt/lib/asan/asan_interceptors.cc:209:3
    #1 0x4d34bb in main /IEC104-master/test/main.c:311:11
    #2 0x7a4124851f44 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x21f44)

SUMMARY: AddressSanitizer: heap-use-after-free /IEC104-master/test/..//IEC10X/Iec10x.c:136:9 in Iec10x_Scheduled
Shadow bytes around the buggy address:
  0x0c0c7fff7fb0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c0c7fff7fc0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c0c7fff7fd0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c0c7fff7fe0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x0c0c7fff7ff0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>0x0c0c7fff8000: fa fa fa fa[fd]fd fd fd fd fd fd fa fa fa fa fa
  0x0c0c7fff8010: fd fd fd fd fd fd fd fa fa fa fa fa fa fa fa fa
  0x0c0c7fff8020: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c0c7fff8030: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c0c7fff8040: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
  0x0c0c7fff8050: fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa fa
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
  Freed heap region:       fd
  Stack left redzone:      f1
  Stack mid redzone:       f2
  Stack right redzone:     f3
  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
  Shadow gap:              cc
==7243==ABORTING