CVE-2024-20355

MEDIUMCVSS 5/10EPSS 0.33%

Last modified

CVE-2024-20355 is a medium-severity vulnerability rated 5/10 on the CVSS scale. 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. EPSS estimates a 0.33% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1
5/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:N

EPSS Probability
0.33%

25.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

VendorProductVersions
CiscoAdaptive Security Appliance Software9.8.2.28
CiscoAdaptive Security Appliance Software9.8.2.33
CiscoAdaptive Security Appliance Software9.8.2.35
CiscoAdaptive Security Appliance Software9.8.2.38
CiscoAdaptive Security Appliance Software9.8.3
CiscoAdaptive Security Appliance Software9.8.3.8
CiscoAdaptive Security Appliance Software9.8.3.11
CiscoAdaptive Security Appliance Software9.8.3.14
CiscoAdaptive Security Appliance Software9.8.3.16
CiscoAdaptive Security Appliance Software9.8.3.18
CiscoAdaptive Security Appliance Software9.8.3.21
CiscoAdaptive Security Appliance Software9.8.3.26
CiscoAdaptive Security Appliance Software9.8.3.29
CiscoAdaptive Security Appliance Software9.8.4
CiscoAdaptive Security Appliance Software9.8.4.3
CiscoAdaptive Security Appliance Software9.8.4.7
CiscoAdaptive Security Appliance Software9.8.4.8
CiscoAdaptive Security Appliance Software9.8.4.10
CiscoAdaptive Security Appliance Software9.8.4.12
CiscoAdaptive Security Appliance Software9.8.4.15
CiscoAdaptive Security Appliance Software9.8.4.17
CiscoAdaptive Security Appliance Software9.8.4.20
CiscoAdaptive Security Appliance Software9.8.4.22
CiscoAdaptive Security Appliance Software9.8.4.25
CiscoAdaptive Security Appliance Software9.8.4.26
CiscoAdaptive Security Appliance Software9.8.4.29
CiscoAdaptive Security Appliance Software9.8.4.32
CiscoAdaptive Security Appliance Software9.8.4.33
CiscoAdaptive Security Appliance Software9.8.4.34
CiscoAdaptive Security Appliance Software9.8.4.35
CiscoAdaptive Security Appliance Software9.8.4.39
CiscoAdaptive Security Appliance Software9.8.4.40
CiscoAdaptive Security Appliance Software9.8.4.41
CiscoAdaptive Security Appliance Software9.8.4.43
CiscoAdaptive Security Appliance Software9.8.4.44
CiscoAdaptive Security Appliance Software9.8.4.45
CiscoAdaptive Security Appliance Software9.8.4.46
CiscoAdaptive Security Appliance Software9.8.4.48
CiscoAdaptive Security Appliance Software9.12.1
CiscoAdaptive Security Appliance Software9.12.1.2
CiscoAdaptive Security Appliance Software9.12.1.3
CiscoAdaptive Security Appliance Software9.12.2
CiscoAdaptive Security Appliance Software9.12.2.1
CiscoAdaptive Security Appliance Software9.12.2.4
CiscoAdaptive Security Appliance Software9.12.2.5
CiscoAdaptive Security Appliance Software9.12.2.9
CiscoAdaptive Security Appliance Software9.12.3
CiscoAdaptive Security Appliance Software9.12.3.2
CiscoAdaptive Security Appliance Software9.12.3.7
CiscoAdaptive Security Appliance Software9.12.3.9

Showing 50 of 227 affected configurations. See NVD for the full list.

References

Timeline

Published
Last Modified
Status
Analyzed

Frequently Asked Questions

What is 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.
How severe is CVE-2024-20355?
CVE-2024-20355 has a CVSS score of 5/10 (MEDIUM severity). The EPSS model estimates a 0.33% probability of exploitation in the next 30 days.
How do I fix CVE-2024-20355?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2024-20355?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST