GHSA-9J5C-2GXV-8M6X
Vulnerability from github – Published: 2026-09-16 21:32 – Updated: 2026-09-16 21:32A vulnerability in the access control list (ACL) Object Group Search (OGS) implementation of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass configured access controls.
This vulnerability is due to a logic error in populating group access control policies (ACPs) with OGS configured. An attacker could exploit this vulnerability by sending traffic that should be blocked through the device. A successful exploit could allow the attacker to bypass access controls and reach devices in protected networks.
{
"affected": [],
"aliases": [
"CVE-2026-20121"
],
"database_specific": {
"cwe_ids": [
"CWE-284"
],
"github_reviewed": false,
"github_reviewed_at": null,
"nvd_published_at": "2026-09-16T21:17:07Z",
"severity": "MODERATE"
},
"details": "A vulnerability in the access control list (ACL) Object Group Search (OGS) implementation of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to bypass configured access controls.\n\nThis vulnerability is due to a logic error in populating group access control policies (ACPs) with OGS configured. An attacker could exploit this vulnerability by sending traffic that should be blocked through the device. A successful exploit could allow the attacker to bypass access controls and reach devices in protected networks.",
"id": "GHSA-9j5c-2gxv-8m6x",
"modified": "2026-09-16T21:32:48Z",
"published": "2026-09-16T21:32:48Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-20121"
},
{
"type": "WEB",
"url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-acl-bypass-8p6vFvw"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N",
"type": "CVSS_V3"
}
]
}
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