Auth bypass in Cisco Adaptive Security Appliance Software
CVE-2024-20355
A vulnerability in the implementation of SAML 2.0 single sign-on (SSO) for remote access VPN services in Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, remote attacker to successfully establish a VPN session on an affected device. This vulnerability is due to improper separation of authorization domains when using SAML authentication. An attacker could exploit this vulnerability by using valid credentials to successfully authenticate using their designated connection profile (tunnel group), intercepting the SAML SSO token that is sent back from the Cisco ASA device, and then submitting the same SAML SSO token to a different tunnel group for authentication. A successful exploit could allow the attacker to establish a remote access VPN session using a connection profile that they are not authorized to use and connect to secured networks behind the affected device that they are not authorized to access. For successful exploitation, the attacker must have valid remote access VPN user credentials.
Vulnerability class: Broken Access Control
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.0 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:N.
EPSS exploit prediction
EPSS: 0.003 (24.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 24th percentile — 24.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
Affected products
- Cisco Adaptive Security Appliance Software — versions 9.8.2.28, 9.8.2.33, 9.8.2.35
- Cisco Adaptive Security Appliance (Asa) Software — versions 9.8.2.28, 9.8.2.33, 9.8.2.35
- Cisco Firepower Threat Defense Software — versions 6.2.3, 6.2.3.1, 6.2.3.2
- Cisco Firepower Threat Defense — versions 6.2.3, 6.2.3.1, 6.2.3.2
- Cisco Secure Firewall Threat Defense — versions 6.2.3, 6.2.3.1, 6.2.3.2
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2024-20355?
- CVE-2024-20355 is a medium-severity vulnerability in Cisco Adaptive Security Appliance Software, classified under Missing Authorization. CVSS score: 5.0/10. Published 2024-05-22.
- How severe is CVE-2024-20355?
- Medium severity. CVSS v3 base score is 5.0 out of 10.