{"id":"CVE-2026-81878","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-81878","generatedAt":"2026-10-28T02:21:49.285Z","title":"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.","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.","published":"2026-09-22T16:18:02.000Z","lastModified":"2026-09-25T16:54:31.000Z","status":"Analyzed","sourceIdentifier":"security-advisories@github.com","cvss":{"version":"3.1","score":5.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H"},"cwe":["CWE-190","CWE-787"],"affected":["radare/radare2"],"epss":{"score":0.00202,"percentile":0.10095,"date":"2026-10-26","history":[{"date":"2026-09-23","score":0.00183,"percentile":0.08103}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.20%). Track it; it rarely justifies an emergency change on its own."},"changes":[{"kind":"new","label":"New CVE","at":"2026-09-22T16:18:02.000Z","detail":{"score":"5.5","severity":"MEDIUM","publishedAt":"2026-09-22T16:18:02.457Z"},"summary":"New CVE, medium severity (CVSS 5.5)."}],"references":[{"url":"https://github.com/radareorg/radare2/commit/6727454b666b28c33837b219a5f91136461357c0","tags":["Patch"],"source":"security-advisories@github.com"},{"url":"https://github.com/radareorg/radare2/issues/26222","tags":["Exploit","Mitigation","Vendor Advisory"],"source":"security-advisories@github.com"},{"url":"https://github.com/radareorg/radare2/pull/26177","tags":["Patch"],"source":"security-advisories@github.com"},{"url":"https://github.com/radareorg/radare2/releases/tag/6.2.0","tags":["Release Notes"],"source":"security-advisories@github.com"},{"url":"https://github.com/radareorg/radare2/security/advisories/GHSA-9phv-v2w8-56j3","tags":["Patch","Vendor Advisory"],"source":"security-advisories@github.com"},{"url":"https://github.com/radareorg/radare2/issues/26222","tags":["Exploit","Mitigation","Vendor Advisory"],"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-81878","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}