CVE-2026-81878

Description

radare2 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.

References

• https://github.com/radareorg/radare2/commit/6727454b666b28c33837b219a5f91136461357c0
• https://github.com/radareorg/radare2/issues/26222
• https://github.com/radareorg/radare2/pull/26177
• https://github.com/radareorg/radare2/releases/tag/6.2.0
• https://github.com/radareorg/radare2/security/advisories/GHSA-9phv-v2w8-56j3