{"id":"CVE-2025-65570","title":"A type confusion in jsish 2.0 allows incorrect control flow during execution of the OP_NEXT opcode","summary":"A type confusion in jsish 2.0 allows incorrect control flow during execution of the OP_NEXT opcode. When an “instanceof” expression uses an array element access as the left-hand operand inside a for-in loop, the instructions implementati…","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-843"],"vendor":"jsish","product":"jsish","affected":["jsish = 2.0"],"published":"2025-12-29","updated":"2026-10-13","sourceUpdated":"2026-10-13T09:10:00.323","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2025-65570","references":[{"url":"https://blog.mcsky.ro/writeups/2025/11/15/inline8-writeup.html","label":"cve@mitre.org"},{"url":"https://blog.mcsky.ro/writeups/2025/11/15/inline8-writeup.html","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"tags":["nvd"],"epss":0.00528,"epssPercentile":0.4306,"ingestedAt":"2026-10-13T09:20:23.169Z","slug":"CVE-2025-65570","body":"## Overview\n\nA type confusion in jsish 2.0 allows incorrect control flow during execution of the OP_NEXT opcode. When an “instanceof” expression uses an array element access as the left-hand operand inside a for-in loop, the instructions implementation leaves an additional array reference on the stack rather than consuming it during OP_INSTANCEOF. As a result, OP_NEXT interprets the array as an iterator object and reads the iterCmd function pointer from an invalid structure, potentially causing a crash or enabling code execution depending on heap layout.\n\n## Affected\n\n- `jsish = 2.0`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"midnight","depthScore":54,"depthScoreParts":{"impact":53.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}