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{"bugzilla": {"description": "firefox: Use-after-free in the JavaScript: WebAssembly component", "id": "2460113", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2460113"}, "csaw": false, "cvss3": {"cvss3_base_score": "6.1", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N", "status": "draft"}, "cwe": "CWE-825", "details": ["A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue:\nUse-after-free in the JavaScript: WebAssembly component"], "name": "CVE-2026-6758", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-04-21T12:40:53Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-6758\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-6758\nhttps://www.mozilla.org/security/advisories/mfsa2026-30/#CVE-2026-6758"], "statement": "Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.", "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[150,*]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Firefox", "source": "cna", "vendor": "Mozilla"}, "product": "firefox", "vendor": "mozilla"}], "analysis": {"en": {"generated_at": "2026-04-27T19:51:05.073636+00:00", "value": {"mitigation_remediation": ["Update Mozilla Firefox to version 150 or later", "Update Mozilla Thunderbird to version 150 or later", "Enable the browser\u2019s auto\u2011update feature so that future patches are applied automatically", "If an immediate update is not possible, use a security policy or extension to disable WebAssembly until the vulnerability is fixed"], "summary": {"action": "Immediate Patch", "impact": "Potential Remote Code Execution"}, "threat_synthesis": {"affected_systems": "Mozilla Firefox and Mozilla Thunderbird are affected. Both products contain the WebAssembly component in their JavaScript engines. The issue was addressed in version 150 of each product, meaning all earlier releases are vulnerable.", "description_and_impact": "A use\u2011after\u2011free flaw (CWE\u2011416) is discovered in the WebAssembly component of the JavaScript engine; the bug leads to memory corruption (CWE\u2011825) that might allow arbitrary code execution within the browser context (inferred). This vulnerability could compromise confidentiality, integrity, and availability by allowing an attacker to run malicious code on the victim\u2019s system.", "risk_and_exploitability": "The EPSS score of 0.00038 (less than 1%) indicates a very low exploitation probability, and the vulnerability is not listed in the KEV catalog, so no verified exploits are known at present. The path to exploitation would likely involve delivering malicious content to the browser, such as a crafted WebAssembly script, and then triggering the use\u2011after\u2011free condition (inferred). The CVSS score of 7.5 indicates high severity based on the ability to execute arbitrary code, but the low EPSS score means the likelihood of real\u2011world use is uncertain."}}}}, "created": "2026-04-21T16:45:15.077469+00:00", "updated": "2026-04-27T20:00:05.653425+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$firefox"]}