Created attachment 14052 [details]
Reproducers.

Build Information:
Wireshark git master.
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The following crash due to a static buffer overflow can be observed in an ASAN build of Wireshark (current git master), by feeding a malformed file to tshark ("$ ./tshark -nVxr /path/to/file"):

Attached are three files which trigger the crash.

--- cut ---
==8089==ERROR: AddressSanitizer: global-buffer-overflow on address 0x00000df60580 at pc 0x000000d6eb8c bp 0x7ffc622f4a80 sp 0x7ffc622f4a78
WRITE of size 1 at 0x00000df60580 thread T0
    #0 0xd6eb8b in my_dgt_tbcd_unpack wireshark/epan/dissectors/packet-gsm_a_common.c:1972:16
    #1 0xd71258 in de_mid wireshark/epan/dissectors/packet-gsm_a_common.c:2270:9
    #2 0x3c7ce02 in dissect_uma_IE wireshark/epan/dissectors/packet-uma.c:912:3
    #3 0x3c7bfd1 in dissect_uma wireshark/epan/dissectors/packet-uma.c:1664:13
    #4 0x1317640 in tcp_dissect_pdus wireshark/epan/dissectors/packet-tcp.c:2740:13
    #5 0x3c7b62b in dissect_uma_tcp wireshark/epan/dissectors/packet-uma.c:1699:2
    #6 0xaf3794 in call_dissector_through_handle wireshark/epan/packet.c:616:8
    #7 0xae5692 in call_dissector_work wireshark/epan/packet.c:691:9
    #8 0xae4e1d in dissector_try_uint_new wireshark/epan/packet.c:1148:9
    #9 0x1318ea7 in decode_tcp_ports wireshark/epan/dissectors/packet-tcp.c:4610:9
    #10 0x131ea52 in process_tcp_payload wireshark/epan/dissectors/packet-tcp.c:4668:13
    #11 0x1319ad8 in dissect_tcp_payload wireshark/epan/dissectors/packet-tcp.c:4743:9
    #12 0x132fb70 in dissect_tcp wireshark/epan/dissectors/packet-tcp.c:5575:13
    #13 0xaf3794 in call_dissector_through_handle wireshark/epan/packet.c:616:8
    #14 0xae5692 in call_dissector_work wireshark/epan/packet.c:691:9
    #15 0xae4e1d in dissector_try_uint_new wireshark/epan/packet.c:1148:9
    #16 0x29c5318 in ip_try_dissect wireshark/epan/dissectors/packet-ip.c:2001:7
    #17 0x29d0521 in dissect_ip_v4 wireshark/epan/dissectors/packet-ip.c:2485:10
    #18 0xaf3794 in call_dissector_through_handle wireshark/epan/packet.c:616:8
    #19 0xae5692 in call_dissector_work wireshark/epan/packet.c:691:9
    #20 0xae4e1d in dissector_try_uint_new wireshark/epan/packet.c:1148:9
    #21 0xae5a38 in dissector_try_uint wireshark/epan/packet.c:1174:9
    #22 0x24e0824 in dissect_ethertype wireshark/epan/dissectors/packet-ethertype.c:307:21
    #23 0xaf3794 in call_dissector_through_handle wireshark/epan/packet.c:616:8
    #24 0xae5692 in call_dissector_work wireshark/epan/packet.c:691:9
    #25 0xaefb1b in call_dissector_only wireshark/epan/packet.c:2662:8
    #26 0xae09f3 in call_dissector_with_data wireshark/epan/packet.c:2675:8
    #27 0x24dc752 in dissect_eth_common wireshark/epan/dissectors/packet-eth.c:545:5
    #28 0x24d499a in dissect_eth_maybefcs wireshark/epan/dissectors/packet-eth.c:828:5
    #29 0xaf3794 in call_dissector_through_handle wireshark/epan/packet.c:616:8
    #30 0xae5692 in call_dissector_work wireshark/epan/packet.c:691:9
    #31 0xae4e1d in dissector_try_uint_new wireshark/epan/packet.c:1148:9
    #32 0x25dca12 in dissect_frame wireshark/epan/dissectors/packet-frame.c:500:11
    #33 0xaf3794 in call_dissector_through_handle wireshark/epan/packet.c:616:8
    #34 0xae5692 in call_dissector_work wireshark/epan/packet.c:691:9
    #35 0xaefb1b in call_dissector_only wireshark/epan/packet.c:2662:8
    #36 0xae09f3 in call_dissector_with_data wireshark/epan/packet.c:2675:8
    #37 0xadffde in dissect_record wireshark/epan/packet.c:501:3
    #38 0xab6d0d in epan_dissect_run_with_taps wireshark/epan/epan.c:373:2
    #39 0x53c91b in process_packet wireshark/tshark.c:3728:5
    #40 0x535d90 in load_cap_file wireshark/tshark.c:3484:11
    #41 0x52c1df in main wireshark/tshark.c:2197:13

0x00000df60580 is located 0 bytes to the right of global variable 'a_bigbuf' defined in 'packet-gsm_a_common.c:762:13' (0xdf60180) of size 1024
SUMMARY: AddressSanitizer: global-buffer-overflow wireshark/epan/dissectors/packet-gsm_a_common.c:1972:16 in my_dgt_tbcd_unpack
Shadow bytes around the buggy address:
  0x000081be4060: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x000081be4070: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x000081be4080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x000081be4090: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x000081be40a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
=>0x000081be40b0:[f9]f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
  0x000081be40c0: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
  0x000081be40d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x000081be40e0: 00 00 00 00 f9 f9 f9 f9 00 00 00 00 00 00 00 00
  0x000081be40f0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  0x000081be4100: 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
==8089==ABORTING
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This bug is subject to a 90 day disclosure deadline. If 90 days elapse without a broadly available patch, then the bug report will automatically become visible to the public.