CVE-2025-20135
published 2025-08-14CVE-2025-20135: A vulnerability in the DHCP client functionality of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense…
PriorityP421medium4.3CVSS 3.1
AVAACLPRNUINSUCNINAL
EPSS
0.20%
9.9th percentile
A vulnerability in the DHCP client functionality of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, adjacent attacker to exhaust available memory.
This vulnerability is due to improper validation of incoming DHCP packets. An attacker could exploit this vulnerability by repeatedly sending crafted DHCPv4 packets to an affected device. A successful exploit could allow the attacker to exhaust available memory, which would affect availability of services and prevent new processes from starting, resulting in a Denial of Service (DoS) condition that would require a manual reboot.
Note: On Cisco Secure FTD Software, this vulnerability does not affect management interfaces.
Affected
301 ranges· showing 25
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
| cisco | cisco_adaptive_security_appliance_software | — | — |
CVSS provenance
nvdv3.14.3MEDIUMCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
vendor_cisco4.3MEDIUM
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Cisco
Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software DHCP Denial of Service Vulnerability
vendor_cisco·2025-08-14·CVSS 4.3
CVE-2025-20135 [MEDIUM] CWE-401 Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software DHCP Denial of Service Vulnerability
Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software DHCP Denial of Service Vulnerability
A vulnerability in the DHCP client functionality of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, adjacent attacker to exhaust available memory.
This vulnerability is due to improper validation of incoming DHCP packets. An attacker could exploit this vulnerability by repeatedly sending crafted DHCPv4 packets to an affected device. A successful exploit could allow the attacker to exhaust available memory, which would affect availability of services and prevent new processes from starting, resulting in a Denial of Service (DoS) condition that would require
Cisco
Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software DHCP Denial of Service Vulnerability
vendor_cisco·CVSS 3.1
CVE-2025-20135 Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software DHCP Denial of Service Vulnerability
CVE-2025-20135: Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense Software DHCP Denial of Service Vulnerability
A vulnerability in the DHCP client functionality of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, adjacent attacker to exhaust available memory. This vulnerability is due to improper validation of incoming DHCP packets. An attacker could exploit this vulnerability by repeatedly sending crafted DHCPv4 packets to an affected device. A successful exploit could allow the attacker to exhaust available memory, which would affect availability of services and prevent new processes from starting, resulting in a Denial of Service (DoS) condition that
GHSA
GHSA-j8qj-frmg-5g7v: A vulnerability in the DHCP client functionality of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat
ghsa_unreviewed·2025-08-14
CVE-2025-20135 [MEDIUM] CWE-401 GHSA-j8qj-frmg-5g7v: A vulnerability in the DHCP client functionality of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat
A vulnerability in the DHCP client functionality of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, adjacent attacker to exhaust available memory.
This vulnerability is due to improper validation of incoming DHCP packets. An attacker could exploit this vulnerability by repeatedly sending crafted DHCPv4 packets to an affected device. A successful exploit could allow the attacker to exhaust available memory, which would affect availability of services and prevent new processes from starting, resulting in a Denial of Service (DoS) condition that would require a manual reboot.
Note: On Cisco Secure FTD Software, this vulnerability does not affect management interfaces.
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2025-08-14
Published