{“lastseen”:””,”description”:”An integer overflow vulnerability exists in the QuickJS regular expression engine (libregexp) due to an inconsistent representation of the bytecode buffer size.\\n\\n * The regular expression bytecode is stored in a DynBuf structure, which correctly uses a $\\\\text{size}\\\\_\\\\text{t}$ (an unsigned type, typically 64-bit) for its size member.\\n\\n\\n * However, several functions, such as re_emit_op_u32 and other internal parsing routines, incorrectly cast or store this DynBuf $\\\\text{size}\\\\_\\\\text{t}$ value into a signed int (typically 32-bit).\\n\\n\\n * When a large or complex regular expression (such as those generated by a recursive pattern in a Proof-of-Concept) causes the bytecode size to exceed $2^{31}$ bytes (the maximum positive value for a signed 32-bit integer), the size value wraps around, resulting in a negative integer when stored in the int variable (Integer Overflow).\\n\\n\\n * This negative value is subsequently used in offset calculations. For example, within functions like re_parse_disjunction, the negative size is used to compute an offset (pos) for patching a jump instruction.\\n\\n\\n * This negative offset is then incorrectly added to the buffer pointer (s-\\u003ebyte\\\\_code.buf + pos), leading to an out-of-bounds write on the first line of the snippet below:\\n\\nput_u32(s-\\u003ebyte_code.buf + pos, len);”,”published”:”2025-10-16T15:51:58.953Z”,”modified”:”2025-10-16T15:51:58.953Z”,”type”:”cve”,”title”:”Type confusion in string addition in QuickJS”,”source”:”Google”,”references”:”https:\/\/bellard.org\/quickjs\/Changelog\\nhttps:\/\/issuetracker.google.com\/434196926″,”id”:”CVE-2025-62495″,”bulletinFamily”:””,”cwe”:[“CWE-191″],”cvelist”:null,”sourceData”:”QuickJS QuickJS 2025-04-26″,”sourceHref”:””,”cvss”:{“score”:7.1,”severity”:”HIGH”,”vector”:”CVSS:4.0\/AV:A\/AC:H\/AT:P\/PR:L\/UI:P\/VC:H\/VI:H\/VA:L\/SC:H\/SI:H\/SA:L”,”version”:”4.0″},”cvss2″:{},”cvss3″:{“version”:””,”vectorString”:””,”baseScore”:0,”baseSeverity”:””,”attackVector”:””,”attackComplexity”:””,”privilegesRequired”:””,”userInteraction”:””,”scope”:””,”confidentialityImpact”:””,”integrityImpact”:””,”availabilityImpact”:””,”cvssV3″:{“version”:””,”vectorString”:””,”baseScore”:0,”baseSeverity”:””,”attackVector”:””,”attackComplexity”:””,”privilegesRequired”:””,”userInteraction”:””,”scope”:””,”confidentialityImpact”:””,”integrityImpact”:””,”availabilityImpact”:””}},”href”:””,”category_name”:”CVE”,”post_link”:””,”product”:”QuickJS”,”version”:”2025-04-26″,”vendor”:”QuickJS”,”ai_description”:””,”ai_severity”:””,”ai_vendor”:””,”ai_product”:””,”ai_version”:””,”ai_score”:0}<\/p>\n","protected":false},"excerpt":{"rendered":"
{“lastseen”:””,”description”:”An integer overflow vulnerability exists in the QuickJS regular expression engine (libregexp) due to an inconsistent representation of the bytecode buffer size.\\n\\n * The regular…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[6,8,50,12,15,13,7,11,5],"class_list":["post-22078","post","type-post","status-publish","format-standard","hentry","category-category_cve","tag-cve","tag-cvss","tag-cvss-71","tag-exploit","tag-high","tag-news","tag-security","tag-tapic","tag-vulnerability"],"yoast_head":"\n