CVE-2023-20095
highpriority · track · 34EPSS 0.006 · 51 %ileDEEURUUSEPSS · scored 2026-10-26
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 cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper handling of HTTPS requests. An attacker could exploit this vulnerability by sending crafted HTTPS requests to an affected system. A successful exploit could allow the attacker to cause resource exhaustion, resulting in a DoS condition.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedCisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.12.4.35 when installed on Cisco Firepower 9000 Seriescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.12.4.39 when installed on Cisco Adaptive Security Virtual Appliance (ASAv)cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.14.4 when installed on Cisco Firepower 9000 Seriescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.1.28 when installed on Cisco Firepower 9000 Seriescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.16.3.14 when installed on Cisco Firepower 9000 Seriescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.8.1 when installed on Cisco Firepower 9000 Seriescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.8.4.20 when installed on Cisco Firepower 9000 Seriescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.8.4.26 when installed on Cisco Firepower 9000 Seriescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco Secure Firewall Adaptive Security Appliance (ASA) Software 9.8.4.3 when installed on Cisco Firepower 9000 Seriescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.9 when installed on Cisco Firepower 2100 Seriescisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - FixedCisco Secure Firewall Threat Defense (FTD) Software 6.4.0.2 when installed on Cisco ASA 5500-X Series Firewallscisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (499)
Products and version ranges known to be affected.
- Cisco ASA (Adaptive Security Appliance)all versionscert_bundDEcpe:/h:cisco:adaptive_security_appliance:-
advisories (2)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2023-2812Cisco Adaptive Security Appliance & Firepower Threat Defense: Mehrere SchwachstellenDeutsch2023-11-01csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Cisco ASA (Adaptive Security Appliance) und Cisco Firepower ausnutzen, um Sicherheitsvorkehrungen zu umgehen oder einen Denial of Service Zustand herbeizuführen.
- cisco-sa-asa-webvpn-dos-3GhZQBASCisco Adaptive Security Appliance Software and Firepower Threat Defense Software Remote Access VPN Denial of Service Vulnerability2023-11-01csaf · cisco_csafUS
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 cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper handling of HTTPS requests. An attacker could exploit this vulnerability by sending crafted HTTPS requests to an affected system. A successful exploit could allow the attacker to cause resource exhaustion, resulting in a DoS condition. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is part of the November 2023 release of the Cisco ASA, FTD, and FMC Security Advisory Bundled publication. For a complete list of the advisories and links to them, see Cisco Event Response: November 2023 Semiannual Cisco ASA, FMC, and FTD Software Security Advisory Bundled Publication ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-74985"].
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (4)
External citations — patches, advisories, analysis.
- https://cxsecurity.com/cveshow/CVE-2023-20095/cnnvd
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asa-webvpn-dos-3GhZQBAScnnvd
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asa-webvpn-dos-3GhZQBASenisa_euvd
- https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asa-webvpn-dos-3GhZQBASVendor Advisorynvd
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