Source: https://bugs.chromium.org/p/project-zero/issues/detail?id=1226
There are three variants of the below crash, all of which stemming from an unbound copy into a fixed size stack buffer allocated in the function ASFParser::SetMetaData, used as an argument to each of the three calls to the function unicodeToUtf_8 without checking that the output length will be less than the size of the buffer. You can see in the crashdump that the argv array has been overwritten by junk unicode output, resulting in the corrupted binary path displayed in the output.
I believe that this issue is mitigated by compiling with stack cookies, so I'm not applying the 90 day deadline to this issue since I don't think it's exploitable except as a denial-of-service.
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Build fingerprint: 'lge/p1_global_com/p1:6.0/MRA58K/1624210305d45:user/release-keys'
Revision: '11'
ABI: 'arm'
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signal 11 (SIGSEGV), code 1 (SEGV_MAPERR), fault addr 0xff951000
r0 ff951002 r1 f023b0ba r2 0000100e r3 ffffff8f
AM write failed: Broken pipe
r4 00000792 r5 f023bfde r6 f5f1c080 r7 efdfca69
r8 f1282348 r9 ff94fc70 sl f1282348 fp 00000012
ip 0000a3c6 sp ff94fc5c lr efdf7457 pc efdf4a9a cpsr 800f0030
backtrace:
#00 pc 00003a9a /system/lib/liblg_parser_asf.so (_Z14unicodeToUtf_8PhPti+85)
#01 pc 00006453 /system/lib/liblg_parser_asf.so (_ZN9ASFParser11SetMetaDataEP15meta_descriptor+186)
#02 pc 6b203432 <unknown>
Proof of Concept:
https://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/42285.zip
