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Fencer Intel
medium 5.3

CVE-2026-20106 json

A vulnerability in the Remote Access SSL VPN, HTTP management and MUS functionality, of Cisco Secure Firewall Adaptive Security Appliance (…

published 8mo ago modified 2mo ago also EUVD-2026-9443

cvss
5.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 31%
public exploits
0
none known

Summary

A vulnerability in the Remote Access SSL VPN, HTTP management and MUS functionality, of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to exhaust device memory resulting in a denial of service (DoS) condition requiring a manual reboot. This vulnerability is due to trusting user input without validation. An attacker could exploit this vulnerability by sending crafted packets to the Remote Access SSL VPN server. A successful exploit could allow the attacker to cause the device to stop responding, resulting in a DoS condition.

Patch / fix

  • cisco secure_firewall_threat_defense 7.0.9, 7.2.11, 7.4.3, 7.6.4, 7.7.11
  • cisco adaptive_security_appliance_software 9.16.4.85, 9.18.4.66, 9.20.4, 9.22.2.4, 9.23.1.7

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CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
8mo ago

Exploit prediction

0.37% chance of exploitation in the next 30 days, higher than 31% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Affected products

  • Cisco Cisco Secure Firewall Adaptive Security Appliance (ASA) Software
  • Cisco Cisco Secure Firewall Threat Defense (FTD) Software

Classification

Weakness
  • CWE-401 Missing Release of Memory after Effective Lifetime

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.