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critical
CVE exact
CVE_2021_21086
What it means
Decrypted Type 1 CharString matches the public callOtherSubr stack-pointer manipulation shape.
Why it fires
CVE-2021-21086 is an out-of-bounds write in Adobe Acrobat/Reader's CoolType Type 1 CharString interpreter. The Project Zero/Faraday analysis describes abusing predefined callOtherSubr handling, especially subroutine 18, to move the operand-stack pointer outside the operand stack and write toward the saved return address. The scanner decrypts Type 1 eexec and CharString data and flags repeated not/get/callOtherSubr bytecode sequences matching the public exploit generator.
Other CVE heuristics
CVE_2026_34621_RELATED CVE_2023_26369 CVE_2026_34621 CVE_2010_1297_FLASH_RICHMEDIA CVE_2010_1297_SWF_TRIGGER CVE_2011_0611_SWF_TRIGGER CVE_2009_1862_FLASH_RICHMEDIA CVE_2010_2883 CVE_2018_4901 CVE_2009_3459 CVE_2018_4990_JPX_EMBEDDED_CMD CVE_2018_4990_JPX_CMAP_TRIGGER CVE_2010_1240 CVE_2010_0188 CVE_2014_0514 CVE_2013_3346 CVE_2013_0640 CVE_2010_3654_FLASH_RICHMEDIA CVE_2007_5020_MAILTO_MSHTA CVE_2014_0496 CVE_2008_2551 CVE_2021_40444 CVE_2006_4694 CVE_2008_0118