CVE-2026-81738

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{"bugzilla": {"description": "openvpn: OpenVPN: Out-of-bounds write via crafted DOMAIN-SEARCH entries", "id": "2529301", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2529301"}, "csaw": false, "cvss3": {"cvss3_base_score": "4.2", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:L", "status": "draft"}, "cwe": "CWE-787", "details": ["A flaw was found in OpenVPN when using the tap-windows6 driver. A remote attacker could exploit this vulnerability by sending specially crafted DOMAIN-SEARCH entries. This could lead to an out-of-bounds write, potentially causing information disclosure or a denial of service."], "name": "CVE-2026-81738", "public_date": "2026-09-07T07:32:20Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-81738\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-81738\nhttps://community.openvpn.net/Security%20Announcements/CVE-2026-81738"], "statement": "This Low impact vulnerability in OpenVPN affects Windows installations utilizing the `tap-windows6` driver. Red Hat products are not directly impacted as they do not deploy OpenVPN with this specific Windows driver.", "threat_severity": "Low"}

{"affected": [{"configurations": [{"platform": ["windows"], "status": "affected", "versions": {"scheme": "semver", "value": "[2.5.0,2.7.6]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "OpenVPN", "source": "cna", "vendor": "OpenVPN"}, "product": "openvpn", "vendor": "openvpn"}], "created": "2026-09-07T15:00:13.658807+00:00", "title": "OpenVPN Windows TAP-Windows6 Out-of-Bounds Write via DOMAIN-SEARCH entries", "updated": "2026-09-07T15:45:17.423895+00:00", "vendors": ["openvpn", "openvpn$PRODUCT$openvpn"]}