Infinite loop in Cisco Adaptive Security Appliance Software
Priority MEDIUM 44CWE-835Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Denial of service
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-835.
Summary
A vulnerability in the function that performs IPv4 and IPv6 Network Address Translation (NAT) DNS inspection 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 an infinite loop condition that occurs when a Cisco Secure ASA or Cisco Secure FTD device processes DNS packets with DNS inspection enabled and the device is configured for NAT44, NAT64, or NAT46. An attacker could exploit this vulnerability by sending crafted DNS packets that match a static NAT rule with DNS inspection enabled through an affected device. A successful exploit could allow the attacker to create an infinite loop and cause the device to reload, resulting in a DoS condition.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00659 51st 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
- Yes
- 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-2025-20136
- 2026-10-03 Alias added: GHSA-w4q8-8r22-vpjc
- 2026-10-25 EPSS moved to the 50th–90th percentile
References
More Cisco vulnerabilities
- TI-2026-74174 Arbitrary file write in Cisco Secure Email Gateway via AMP feature KEVCVSS 3.1CRITICAL 9.8
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- TI-2026-53489 Cisco Secure Email Gateway SQL Injection Vulnerability KEVCVSS 3.1CRITICAL 9.8
- 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-2025-20136 · CVE Program
- CVE-2025-20136 · NVD
- FIRST EPSS
- GHSA-w4q8-8r22-vpjc · 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