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CVE-2026-20082

Cisco Adaptive Security Appliance Software vulnerability

8.6 HIGHEPSS 0.42%
  1. Published4 Mar 2026

Description

A vulnerability in the handling of the embryonic connection limits in Cisco Secure Firewall Adaptive Security Appliance (ASA) Software could allow an unauthenticated, remote attacker to cause incoming TCP SYN packets to be dropped incorrectly. This vulnerability is due to improper handling of new, incoming TCP connections that are destined to management or data interfaces when the device is under a TCP SYN flood attack. An attacker could exploit this vulnerability by sending a crafted stream of traffic to an affected device. A successful exploit could allow the attacker to prevent all incoming TCP connections to the device from being established, including remote management access, Remote Access VPN (RAVPN) connections, and all network protocols that are TCP-based. This results in a denial of service (DoS) condition for affected features.

CVSS 3.1 breakdown

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
ScopeChanged
ConfidentialityNone
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Affected products

Cisco Adaptive Security Appliance Software≥ 9.20.4.14 < 9.20.4.19

Remediation

Fixed in
Cisco Adaptive Security Appliance Software≥ 9.20.4.19

References

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Frequently asked

Is CVE-2026-20082 being actively exploited?

CVE-2026-20082 is not in the CISA KEV catalog. Its EPSS exploit probability is 0.42%.

How severe is CVE-2026-20082?

CVE-2026-20082 has a CVSS 3.1 base score of 8.6, rated high. EPSS estimates a 0.42% probability of exploitation.

Which products are affected by CVE-2026-20082?

Affected products include Cisco Adaptive Security Appliance Software.

How do I fix CVE-2026-20082?

Upgrade affected software to a fixed version, for example Cisco Adaptive Security Appliance Software 9.20.4.19 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2026-20082 against the real software inventory on every managed device, as each hourly inventory arrives. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.