Cisco Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) Heap Inspection Vulnerability

A vulnerability in the Remote Access SSL VPN service for Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition.  This vulnerability is due to insufficient error checking when processing HTTP requests. An attacker could exploit this vulnerability by sending a crafted HTTP request to the Remote Access SSL VPN service on an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition.

Ein entfernter, anonymer Angreifer kann eine Schwachstelle in Cisco ASA (Adaptive Security Appliance) und Cisco Secure Firewall Threat Defense ausnutzen, um einen Denial of Service Angriff durchzuführen.

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As of August 11, 2026, Cisco is affected by a vulnerability in the following products: On August 11, 2026, Cybersecurity and Infrastructure Security Agency (CISA) added CVE-2026-20349 to their Known Exploited Vulnerabilities (KEV) Database.

Une vulnérabilité a été découverte dans les produits Cisco. Elle permet à un attaquant de provoquer un déni de service à distance. Cisco indique que la vulnérabilité CVE-2026-20349 est activement exploitée.

Nel dettaglio, la vulnerabilità identificata tramite la CVE-2026-20349 –di tipo " Improper Control of Generation of Code " e con punteggio CVSS 3.1: 8.6– riguarda il servizio Remote Access SSL VPN di Cisco Secure Firewall ASA e Cisco Secure Firewall FTD ed è causata da controlli insufficienti durante l'elaborazione di specifiche richieste HTTP. In particolare, un attaccante remoto non autenticato potrebbe sfruttare la vulnerabilità inviando richieste HTTP appositamente predisposte verso il servizio SSL VPN esposto causando il riavvio del dispositivo e determinando una condizione di Denial of Service (DoS) e, quindi, conseguente interruzione dell'accesso remoto e dei servizi di sicurezza erogati.

Cisco Secure Firewall Adaptive Security Appliance（ASA）ソフトウェアおよびCisco Secure Firewall Threat Defense（FTD）ソフトウェアのリモートアクセスSSL VPNサービスにおける脆弱性により、認証されていないリモートの攻撃者がデバイスを予期せず再起動させることが可能となり、サービス拒否（DoS）状態を引き起こす可能性があります。この脆弱性はHTTPリクエストの処理時にエラーチェックが不十分であることに起因しています。攻撃者は細工されたHTTPリクエストを影響を受けるデバイスのリモートアクセスSSL VPNサービスに送信することで、この脆弱性を悪用できます。成功した攻撃によって影響を受けるデバイスが再起動し、DoS状態を引き起こす可能性があります。

Cisco Secure Firewall Adaptive Security Appliance(ASA) Software, Cisco Secure Firewall Threat Defense(FTD) Software에서 발생하는 Heap Inspection 취약점(CVE-2026-20349) [1][2]

Cisco Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) Heap Inspection Vulnerability

A heap inspection vulnerability in Cisco Secure Firewall ASA and FTD's Remote Access SSL VPN service allows unauthenticated remote attackers to send crafted HTTP requests causing device reloads and denial of service.