Cisco Adaptive Security Appliance and Firepower Threat Defense Software DHCP Denial of Service Vulnerability
Priority LOW 19CWE-401Published · Updated
Key facts
- Attack vector
- Adjacent network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · Low
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-401.
Summary
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.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00217 12th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Cisco | Cisco Adaptive Security Appliance (ASA) Software | 9.12.3; 9.8.3; 9.12.1; 9.8.1; 9.12.2; 9.8.2.45; 9.8.2; 9.8.4; 9.14.1; 9.12.4; 9.8.2.26; 9.8.2.24; 9.8.2.15; 9.8.2.14; 9.8.2.35; 9.8.2.20; 9.8.2.8; 9.8.2.17; 9.8.2.28; 9.8.2.33; 9.8.2.38; 9.8.4.25; 9.12.3.2; 9.12.3.7; 9.8.3.18; 9.8.3.14; 9.8.4.15; 9.8.4.8; 9.8.1.7; 9.8.3.29; 9.14.1.10; 9.12.2.5; 9.8.4.22; 9.12.3.12; 9.8.4.7; 9.8.4.17; 9.8.3.16; 9.8.4.20; 9.8.3.11; 9.12.1.3; 9.8.4.3; 9.12.2.4; 9.8.4.12; 9.12.1.2; 9.8.3.26; 9.8.1.5; 9.12.2.9; 9.12.3.9; 9.8.3.21; 9.8.4.10; 9.12.2.1; 9.12.4.2; 9.14.1.6; 9.8.3.8; 9.14.1.15; 9.14.1.19; 9.8.4.26; 9.12.4.4; 9.14.1.30; 9.8.4.29; 9.12.4.7; 9.14.2; 9.12.4.8; 9.8.4.32; 9.12.4.10; 9.14.2.4; 9.14.2.8; 9.12.4.13; 9.8.4.33; 9.14.2.13; 9.8.4.34; 9.12.4.18; 9.8.4.35; 9.14.2.15; 9.12.4.24; 9.16.1; 9.8.4.39; 9.14.3; 9.12.4.26; 9.16.1.28; 9.14.3.1; 9.12.4.29; 9.14.3.9; 9.16.2; 9.12.4.30; 9.16.2.3; 9.8.4.40; 9.14.3.11; 9.12.4.35; 9.8.4.41; 9.15.1.1; 9.14.3.13; 9.16.2.7; 9.12.4.37; 9.14.3.15; 9.17.1; 9.16.2.11; 9.14.3.18; 9.16.2.13; 9.12.4.39; 9.12.4.38; 9.8.4.43; 9.14.4; 9.16.2.14; 9.17.1.7; 9.12.4.40; 9.16.3.3; 9.14.4.6; 9.16.3; 9.16.3.14; 9.17.1.9; 9.14.4.7; 9.12.4.41; 9.17.1.10; 9.8.4.44; 9.18.1; 9.12.4.47; 9.14.4.12; 9.16.3.15; 9.18.1.3; 9.17.1.11; 9.12.4.48; 9.14.4.13; 9.18.2; 9.16.3.19; 9.17.1.13; 9.12.4.50; 9.14.4.14; 9.17.1.15; 9.8.4.45; 9.12.4.52; 9.14.4.15; 9.16.3.23; 9.18.2.5; 9.16.4; 9.12.4.54; 9.14.4.17; 9.8.4.46; 9.17.1.20; 9.18.2.7; 9.19.1; 9.16.4.9; 9.12.4.55; 9.18.2.8; 9.14.4.22; 9.16.4.14; 9.8.4.48; 9.18.3; 9.19.1.5; 9.14.4.23; 9.12.4.56; 9.16.4.18; 9.17.1.30; 9.19.1.9; 9.18.3.39; 9.16.4.19; 9.12.4.58; 9.19.1.12; 9.18.3.46; 9.16.4.27; 9.19.1.18; 9.18.3.53; 9.18.3.55; 9.16.4.38; 9.17.1.33; 9.12.4.62; 9.16.4.39; 9.18.3.56; 9.20.1; 9.16.4.42; 9.19.1.22; 9.18.4; 9.20.1.5; 9.18.4.5; 9.19.1.24; 9.16.4.48; 9.18.4.8; 9.20.2; 9.19.1.27; 9.12.4.65; 9.16.4.55; 9.18.4.22; 9.20.2.10; 9.16.4.57; 9.19.1.28; 9.17.1.39; 9.12.4.67; 9.14.4.24; 9.18.4.24; 9.20.2.21; 9.16.4.61; 9.19.1.31; 9.18.4.29; 9.20.2.22; 9.16.4.62; 9.18.4.34; 9.20.3; 9.16.4.67; 9.16.4.70; 9.18.4.40; 9.22.1.1; 9.16.4.71; 9.20.3.4; 9.18.4.47; 9.17.1.45; 9.19.1.37; 9.17.1.46; 9.19.1.38; 9.22.1.2 | — | No fix listed | CNA |
| Cisco | Cisco Firepower Threat Defense Software | 6.2.3.14; 6.4.0.1; 6.2.3.7; 6.2.3; 6.4.0.2; 6.2.3.9; 6.2.3.1; 6.2.3.2; 6.4.0.5; 6.2.3.10; 6.4.0; 6.4.0.3; 6.2.3.6; 6.4.0.4; 6.2.3.15; 6.2.3.5; 6.2.3.4; 6.2.3.3; 6.2.3.8; 6.4.0.6; 6.2.3.11; 6.2.3.12; 6.2.3.13; 6.4.0.7; 6.4.0.8; 6.6.0; 6.4.0.9; 6.2.3.16; 6.6.0.1; 6.6.1; 6.4.0.10; 6.4.0.11; 6.6.3; 6.6.4; 6.4.0.12; 7.0.0; 6.2.3.17; 7.0.0.1; 6.6.5; 7.0.1; 7.1.0; 6.4.0.13; 6.6.5.1; 6.2.3.18; 7.0.1.1; 6.4.0.14; 7.1.0.1; 6.6.5.2; 7.0.2; 6.4.0.15; 7.2.0; 7.0.2.1; 7.0.3; 6.6.7; 7.1.0.2; 7.2.0.1; 7.0.4; 7.2.1; 7.0.5; 6.4.0.16; 7.3.0; 7.2.2; 7.2.3; 6.6.7.1; 7.3.1; 7.1.0.3; 7.2.4; 7.0.6; 7.2.5; 7.2.4.1; 7.3.1.1; 7.4.0; 6.4.0.17; 7.0.6.1; 7.2.5.1; 7.4.1; 7.2.6; 7.0.6.2; 7.4.1.1; 6.6.7.2; 6.4.0.18; 7.2.7; 7.2.5.2; 7.3.1.2; 7.2.8; 7.6.0; 7.4.2; 7.2.8.1; 7.0.6.3; 7.4.2.1; 7.2.9 | — | No fix listed | CNA |
- Cisco Adaptive Security Appliance (ASA) Software VendorCisco Affected 9.12.3; 9.8.3; 9.12.1; 9.8.1; 9.12.2; 9.8.2.45; 9.8.2; 9.8.4; 9.14.1; 9.12.4; 9.8.2.26; 9.8.2.24; 9.8.2.15; 9.8.2.14; 9.8.2.35; 9.8.2.20; 9.8.2.8; 9.8.2.17; 9.8.2.28; 9.8.2.33; 9.8.2.38; 9.8.4.25; 9.12.3.2; 9.12.3.7; 9.8.3.18; 9.8.3.14; 9.8.4.15; 9.8.4.8; 9.8.1.7; 9.8.3.29; 9.14.1.10; 9.12.2.5; 9.8.4.22; 9.12.3.12; 9.8.4.7; 9.8.4.17; 9.8.3.16; 9.8.4.20; 9.8.3.11; 9.12.1.3; 9.8.4.3; 9.12.2.4; 9.8.4.12; 9.12.1.2; 9.8.3.26; 9.8.1.5; 9.12.2.9; 9.12.3.9; 9.8.3.21; 9.8.4.10; 9.12.2.1; 9.12.4.2; 9.14.1.6; 9.8.3.8; 9.14.1.15; 9.14.1.19; 9.8.4.26; 9.12.4.4; 9.14.1.30; 9.8.4.29; 9.12.4.7; 9.14.2; 9.12.4.8; 9.8.4.32; 9.12.4.10; 9.14.2.4; 9.14.2.8; 9.12.4.13; 9.8.4.33; 9.14.2.13; 9.8.4.34; 9.12.4.18; 9.8.4.35; 9.14.2.15; 9.12.4.24; 9.16.1; 9.8.4.39; 9.14.3; 9.12.4.26; 9.16.1.28; 9.14.3.1; 9.12.4.29; 9.14.3.9; 9.16.2; 9.12.4.30; 9.16.2.3; 9.8.4.40; 9.14.3.11; 9.12.4.35; 9.8.4.41; 9.15.1.1; 9.14.3.13; 9.16.2.7; 9.12.4.37; 9.14.3.15; 9.17.1; 9.16.2.11; 9.14.3.18; 9.16.2.13; 9.12.4.39; 9.12.4.38; 9.8.4.43; 9.14.4; 9.16.2.14; 9.17.1.7; 9.12.4.40; 9.16.3.3; 9.14.4.6; 9.16.3; 9.16.3.14; 9.17.1.9; 9.14.4.7; 9.12.4.41; 9.17.1.10; 9.8.4.44; 9.18.1; 9.12.4.47; 9.14.4.12; 9.16.3.15; 9.18.1.3; 9.17.1.11; 9.12.4.48; 9.14.4.13; 9.18.2; 9.16.3.19; 9.17.1.13; 9.12.4.50; 9.14.4.14; 9.17.1.15; 9.8.4.45; 9.12.4.52; 9.14.4.15; 9.16.3.23; 9.18.2.5; 9.16.4; 9.12.4.54; 9.14.4.17; 9.8.4.46; 9.17.1.20; 9.18.2.7; 9.19.1; 9.16.4.9; 9.12.4.55; 9.18.2.8; 9.14.4.22; 9.16.4.14; 9.8.4.48; 9.18.3; 9.19.1.5; 9.14.4.23; 9.12.4.56; 9.16.4.18; 9.17.1.30; 9.19.1.9; 9.18.3.39; 9.16.4.19; 9.12.4.58; 9.19.1.12; 9.18.3.46; 9.16.4.27; 9.19.1.18; 9.18.3.53; 9.18.3.55; 9.16.4.38; 9.17.1.33; 9.12.4.62; 9.16.4.39; 9.18.3.56; 9.20.1; 9.16.4.42; 9.19.1.22; 9.18.4; 9.20.1.5; 9.18.4.5; 9.19.1.24; 9.16.4.48; 9.18.4.8; 9.20.2; 9.19.1.27; 9.12.4.65; 9.16.4.55; 9.18.4.22; 9.20.2.10; 9.16.4.57; 9.19.1.28; 9.17.1.39; 9.12.4.67; 9.14.4.24; 9.18.4.24; 9.20.2.21; 9.16.4.61; 9.19.1.31; 9.18.4.29; 9.20.2.22; 9.16.4.62; 9.18.4.34; 9.20.3; 9.16.4.67; 9.16.4.70; 9.18.4.40; 9.22.1.1; 9.16.4.71; 9.20.3.4; 9.18.4.47; 9.17.1.45; 9.19.1.37; 9.17.1.46; 9.19.1.38; 9.22.1.2 Fixed in — No fix listed CNA
- Cisco Firepower Threat Defense Software VendorCisco Affected 6.2.3.14; 6.4.0.1; 6.2.3.7; 6.2.3; 6.4.0.2; 6.2.3.9; 6.2.3.1; 6.2.3.2; 6.4.0.5; 6.2.3.10; 6.4.0; 6.4.0.3; 6.2.3.6; 6.4.0.4; 6.2.3.15; 6.2.3.5; 6.2.3.4; 6.2.3.3; 6.2.3.8; 6.4.0.6; 6.2.3.11; 6.2.3.12; 6.2.3.13; 6.4.0.7; 6.4.0.8; 6.6.0; 6.4.0.9; 6.2.3.16; 6.6.0.1; 6.6.1; 6.4.0.10; 6.4.0.11; 6.6.3; 6.6.4; 6.4.0.12; 7.0.0; 6.2.3.17; 7.0.0.1; 6.6.5; 7.0.1; 7.1.0; 6.4.0.13; 6.6.5.1; 6.2.3.18; 7.0.1.1; 6.4.0.14; 7.1.0.1; 6.6.5.2; 7.0.2; 6.4.0.15; 7.2.0; 7.0.2.1; 7.0.3; 6.6.7; 7.1.0.2; 7.2.0.1; 7.0.4; 7.2.1; 7.0.5; 6.4.0.16; 7.3.0; 7.2.2; 7.2.3; 6.6.7.1; 7.3.1; 7.1.0.3; 7.2.4; 7.0.6; 7.2.5; 7.2.4.1; 7.3.1.1; 7.4.0; 6.4.0.17; 7.0.6.1; 7.2.5.1; 7.4.1; 7.2.6; 7.0.6.2; 7.4.1.1; 6.6.7.2; 6.4.0.18; 7.2.7; 7.2.5.2; 7.3.1.2; 7.2.8; 7.6.0; 7.4.2; 7.2.8.1; 7.0.6.3; 7.4.2.1; 7.2.9 Fixed in — No fix listed CNA
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2025-20135
- 2026-10-03 Alias added: GHSA-j8qj-frmg-5g7v
References
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- TI-2026-53488 Cisco Identity Services Engine Authentication Bypass Vulnerability KEVCVSS 3.1CRITICAL 10.0
- TI-2026-16388 Cisco Catalyst SD-WAN Controller Authentication Bypass Vulnerability KEVCVSS 3.1CRITICAL 10.0
- TI-2026-16344 Cisco Secure Firewall Management Center Software Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 10.0
Sources
- CVE-2025-20135 · CVE Program
- CVE-2025-20135 · NVD
- FIRST EPSS
- GHSA-j8qj-frmg-5g7v · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences