How severe is CVE-2026-20106?

CVE-2026-20106 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2026-20106 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-20106?

CVE-2026-20106 primarily affects Cisco Adaptive Security Appliance Software. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2026-20106?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-20106 have an EU (EUVD) identifier?

Yes. CVE-2026-20106 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-9443.

When was CVE-2026-20106 published?

CVE-2026-20106 was published on 2026-03-04 and last updated on 2026-06-17.

CVE-2026-20106

CVE-2026-20106 is a medium-severity vulnerability in Cisco Adaptive Security Appliance Software with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-401.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 0% (24th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-9443
Weakness: CWE-401
Affected product: Cisco Adaptive Security Appliance Software
Published: 2026-03-04
Last modified: 2026-06-17

Description

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.

Frequently asked questions

What is CVE-2026-20106?: 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.
How severe is CVE-2026-20106?: CVE-2026-20106 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2026-20106 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (24th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-20106?: CVE-2026-20106 primarily affects Cisco Adaptive Security Appliance Software. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2026-20106?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-20106 have an EU (EUVD) identifier?: Yes. CVE-2026-20106 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-9443.
When was CVE-2026-20106 published?: CVE-2026-20106 was published on 2026-03-04 and last updated on 2026-06-17.

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asaftd-vpn-m9sx6MbC

Affected products (2)

cpe:2.3:o:cisco:adaptive_security_appliance_software:*:*:*:*:*:*:*:*
cpe:2.3:a:cisco:firepower_threat_defense_software:*:*:*:*:*:*:*:*

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