--- id: "CVE-2023-20269" kind: "vulnerability" aliases: ["CVE-2023-20269"] title: "cisco adaptive security appliance software: A vulnerability in the remote access VPN feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco\u2026" severity: "critical" cvss: 9.1 epss: null exploited: true status: "open" category: "infrastructure" products: [{"name": "Cisco Adaptive Security Appliance and Firepower Threat Defense", "fixed": [], "affected": "", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.1", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.1.5", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.1.7", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.2", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.2.8", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.2.14", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.2.15", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.2.17", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.2.20", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.2.24", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.2.26", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.2.28", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.2.33", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.2.35", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.2.38", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.3", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.3.8", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.3.11", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.3.14", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.3.16", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.3.18", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.3.21", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.3.26", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.3.29", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.4", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.4.3", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.4.7", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.4.8", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.4.10", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.4.12", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.4.15", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.4.17", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.4.20", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.4.22", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.4.25", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.4.26", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.4.29", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.4.32", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.4.33", "ecosystem": "vendor"}, {"name": "cisco adaptive security appliance software", "fixed": [], "affected": "= 9.8.4.34", "ecosystem": "vendor"}] ecosystems: ["vendor"] tags: ["asa", "cisco", "clientless-ssl-vpn", "exploited", "firepower", "infrastructure", "ransomware", "self-hosted"] not_affected_if: ["managed-hosting", "no-clientless-ssl-vpn"] published_at: "2023-09-06T18:15:08+00:00" first_seen_at: "2026-10-23T19:11:51+00:00" updated_at: "2026-10-23T22:29:04+00:00" sources: [{"source": "kev", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2023-20269", "first_seen_at": "2026-10-23T19:11:51+00:00"}, {"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2023-20269", "first_seen_at": "2026-10-23T22:29:04+00:00"}] --- # cisco adaptive security appliance software: A vulnerability in the remote access VPN feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco… Cisco ASA and Firepower Threat Defense firewalls contain an unauthorized access flaw that lets an unauthenticated remote attacker brute-force valid username and password pairs or open a clientless SSL VPN session as an unauthorized user. CISA lists it as known exploited, with ransomware use noted in its catalog tags. _Summary, check and fix written by a model from the sources; labelled as such._ ## Affected - vendor:Cisco Adaptive Security Appliance and Firepower Threat Defense affected ? fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.1 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.1.5 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.1.7 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.2 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.2.8 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.2.14 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.2.15 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.2.17 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.2.20 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.2.24 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.2.26 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.2.28 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.2.33 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.2.35 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.2.38 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.3 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.3.8 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.3.11 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.3.14 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.3.16 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.3.18 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.3.21 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.3.26 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.3.29 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.4 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.4.3 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.4.7 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.4.8 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.4.10 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.4.12 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.4.15 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.4.17 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.4.20 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.4.22 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.4.25 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.4.26 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.4.29 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.4.32 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.4.33 fixed ? - vendor:cisco adaptive security appliance software affected = 9.8.4.34 fixed ? ## Fix Apply the vendor mitigations for group-lock and vpn-simultaneous-logins per Cisco's advisory, or retire unsupported devices. Exact fixed versions: unknown from sources. ## Timeline - 2026-10-23T19:11:51+00:00 kev https://www.cisa.gov/known-exploited-vulnerabilities-catalog?search_api_fulltext=CVE-2023-20269 - 2026-10-23T22:29:04+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2023-20269 ## From the sources A vulnerability in the remote access VPN feature of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to conduct a brute force attack in an attempt to identify valid username and password combinations or an authenticated, remote attacker to establish a clientless SSL VPN session with an unauthorized user. This vulnerability is due to improper separation of authentication, authorization, and accounting (AAA) between the remote access VPN feature and the HTTPS management and site-to-site VPN features. An attacker could exploit this vulnerability by specifying a default connection profile/tunnel group while conducting a brute force attack or while establishing a clientless SSL VPN session using valid credentials. A successful exploit could allow the attacker to achieve one or both of the following: Identify valid credentials that could then be used to establish an unauthorized remote access VPN session. Establish a clientless SSL VPN session (only when running Cisco ASA Software Release 9.16 or earlier). Notes: Establishing a client-based remote access VPN tunnel is not possible as these default connection profiles/tunnel groups do not and cannot have an IP address pool configured. This vulnerability does not allow an attacker to bypass authentication. To successfully establish a remote access VPN session, valid credentials are required, including a valid second factor if multi-factor authentication (MFA) is configured. Cisco will release software updates that address this vulnerability. There are workarounds that address this vulnerability. --- _Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_