Reference page — cumulative record through Saturday, October 3, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-81878

CVE-2026-81878MEDIUM

radareorg radare2 — radare2: Integer overflow causes heap out-of-bounds write in radare2 PYC parser

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   L   L   N   R  U  N  N  H    5.5   .0020    9.2     —

AFFECTED
  Product  Versions   Fixed
  radare2  < 6.2.0 –  —

TIMELINE
  Aug 27  Reserved by GitHub_M
  Sep 22  Published (CNA: GitHub_M)
  Sep 25  EXPLOIT PUBLISHED — CVE-2026-81878 (radareorg radare2). Public exploit reference added.

CWE-190, CWE-787 · CNA: GitHub_M · CVSS v3.1 · 5 references · NVD status: Analyzed

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.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
August 27, 2026	Reserved	Reserved by GitHub_M
September 22, 2026	Published	Published (CNA: GitHub_M)
September 25, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-81878 (radareorg radare2). Public exploit reference added.

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
radareorg	radare2	—	< 6.2.0	—

Weaknesses

CWE-190 · CWE-787

References (5)

https://github.com/radareorg/radare2/commit/6727454b666b28c33837b219a5f91136461357c0 [Patch]
https://github.com/radareorg/radare2/issues/26222 [Exploit, Mitigation, Vendor Advisory]
https://github.com/radareorg/radare2/pull/26177 [Patch]
https://github.com/radareorg/radare2/releases/tag/6.2.0 [Release Notes]
https://github.com/radareorg/radare2/security/advisories/GHSA-9phv-v2w8-56j3 [Patch, Vendor Advisory]

Authoritative record: CVE-2026-81878 at cve.org

Vendors: radareorg

Weaknesses: CWE-190 · CWE-787

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-81878 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Saturday, October 3, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.