CVE-2026-34626

// Conceptual Proof of Concept for Prototype Pollution in Acrobat Reader // This script demonstrates the basic mechanism of polluting the prototype // Hypothetical vulnerable function in the target environment function vulnerableMerge(target, source) { for (const key in source) { if (source.hasOwnProperty(key)) { target[key] = source[key]; // Vulnerable to __proto__ pollution in some JS engines/contexts } } } // Malicious payload designed to pollute the object prototype var payload = JSON.parse('{"__proto__": {"maliciousProperty": "exploited", "customPath": "/etc/passwd"}}'); // Victim object that will be merged with the payload var victimObj = {}; // Trigger the pollution vulnerableMerge(victimObj, payload); // Verification step if ({}.maliciousProperty === "exploited") { console.log("[+] Prototype Pollution Successful!"); // Hypothetical execution flow leading to file read based on polluted property app.alert("Prototype pollution confirmed. Potential for arbitrary file read exists."); } else { console.log("[-] Exploit failed"); }

{"cve": {"id": "CVE-2026-34626", "sourceIdentifier": "[email protected]", "published": "2026-04-14T17:16:51.283", "lastModified": "2026-04-16T14:14:59.690", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "Acrobat Reader versions 26.001.21411, 24.001.30360, 24.001.30362 and earlier are affected by an Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution') vulnerability that could result in arbitrary file system read in the context of the current user. Exploitation of this issue requires user interaction in that a victim must open a malicious file."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N", "baseScore": 6.3, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "REQUIRED", "scope": "CHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "availabilityImpact": "NONE"}, "exploitabilityScore": 1.8, "impactScore": 4.0}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-1321"}]}], "configurations": [{"operator": "AND", "nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:adobe:acrobat:*:*:*:*:classic:*:*:*", "versionStartIncluding": "24.0.0", "versionEndExcluding": "24.001.30365", "matchCriteriaId": "7E334D1F-0A7E-45F0-AE1C-AE3F38647E17"}, {"vulnerable": true, "criteria": "cpe:2.3:a:adobe:acrobat_dc:*:*:*:*:continuous:*:*:*", "versionStartIncluding": "15.008.20082", "versionEndExcluding": "26.001.21431", "matchCriteriaId": "131CFDA9-0739-4C00-9B10-0F20C3979B22"}, {"vulnerable": true, "criteria": "cpe:2.3:a:adobe:acrobat_reader_dc:*:*:*:*:continuous:*:*:*", "versionStartIncluding": "15.008.20082", "versionEndExcluding": "26.001.21431", "matchCriteriaId": "EB130846-ED6A-4C3E-8984-685EEA001AAF"}]}, {"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": false, "criteria": "cpe:2.3:o:apple:macos:-:*:*:*:*:*:*:*", "matchCriteriaId": "387021A0-AF36-463C-A605-32EA7DAC172E"}, {"vulnerable": false, "criteria": "cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:*", "matchCriteriaId": "A2572D17-1DE6-457B-99CC-64AFD54487EA"}]}]}], "references": [{"url": "https://helpx.adobe.com/security/products/acrobat/apsb26-44.html", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}