CVE-2026-20009

MEDIUM

CVSS v3.1: 5.3 · EPSS: 0.0004 (12.0 percentile)

NetworkNo privilegesNo user interactionVendor advisory ref

Source data as of:

At a glance

Severity
MEDIUM
CVSS
5.3 v3.1 · NVD
EPSS
0.0004 (12.0 percentile) · FIRST.org
CISA KEV
No
Attack conditions (CVSS vector)
NetworkNo privilegesNo user interaction · Source: NVD Vector
Affected vendors
cisco
Published
2026-03-04 · Modified: 2026-04-16

CVSS / EPSS / KEV

CVSS v3.1 5.3 / 10 MEDIUM Source: NVD
EPSS 0.0004 12.0 percentile Source: FIRST.org
CISA KEV No Source: CISA

Source — CVSS: NVD · EPSS: FIRST.org · KEV: CISA. Data & Sources

Description

A vulnerability in the implementation of the proprietary SSH stack with SSH key-based authentication in Cisco Secure Firewall Adaptive Security Appliance (ASA) Software could allow an unauthenticated, remote attacker to log in to a Cisco Secure Firewall ASA device and execute commands as a specific user. This vulnerability is due to insufficient validation of user input during the SSH authentication phase. An attacker could exploit this vulnerability by submitting crafted input during SSH authentication to an affected device. A successful exploit could allow the attacker to log in to the device as a specific user without the private SSH key of that user. To exploit this vulnerability, the attacker must possess a valid username and the associated public key. The private key is not required. Notes: Exploitation of this vulnerability does not provide the attacker with root access. The authentication, authorization, and accounting (AAA) configuration command auto-enable is not affected by this vulnerability.  

Record details

CVE ID
CVE-2026-20009
CVSS (v3.1)
5.3 (MEDIUM)
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
Exploitability subscore
3.9
Impact subscore
1.4
EPSS
0.0004 (12.0 percentile) — 2026-04-17
CISA KEV
No
Weakness (CWE)
CWE-138
Affected vendors
cisco
Affected configurations (CPE)
4
Published
2026-03-04
Modified
2026-04-16
Status
Analyzed

References

Reference URLs as listed by NVD, grouped by a mechanical match on the link's host/pattern. Labels describe the link type only.