CVE-2026-81878

medium

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/security/advisories/GHSA-9phv-v2w8-56j3

https://github.com/radareorg/radare2/releases/tag/6.2.0

https://github.com/radareorg/radare2/pull/26177

https://github.com/radareorg/radare2/issues/26222

https://github.com/radareorg/radare2/commit/6727454b666b28c33837b219a5f91136461357c0

Details

Source: Mitre, NVD

Published: 2026-09-22

Updated: 2026-09-25

Risk Information

CVSS v2

Base Score: 4.9

Vector: CVSS2#AV:L/AC:L/Au:N/C:N/I:N/A:C

Severity: Medium

CVSS v3

Base Score: 5.5

Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Severity: Medium

EPSS

EPSS: 0.00183