23 Oct 2026 15:48:27 UTC
radare2: Integer overflow causes heap out-of-bounds write in radare2 PYC parser
cve-program · CVE-2026-81878 · Published
CVE-2026-81878
radare2: Integer overflow causes heap out-of-bounds write in radare2 PYC parser
CVSS 3.1 5.5 MEDIUMCheck source for fixed versionsKEV status unknown
cve-program · CVE-2026-81878
Publishedradare2 is a UNIX-like reverse engineering framework and command-line toolset. Prior to 6.2.0, radare2's CPython bytecode .pyc marshal parser was vulnerable because the CPython marshal readers accepted a 32-bit string length without rejecting values that overflow the size-plus-one allocation. The vulnerability is triggered by opening or inspecting a crafted .pyc file through r2 or rabin2. A length of 0xffffffff wrapped the allocation to zero before the common byte reader wrote attacker-controlled data and fill bytes beyond the heap allocation. This can cause heap memory corruption and denial of service; arbitrary code execution is possible but has not been demonstrated. This issue is fixed in version 6.2.0.
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