CVE-2024-20508: unified threat Heap Overflow — Fix

Description

A vulnerability in Cisco Unified Threat Defense (UTD) Snort Intrusion Prevention System (IPS) Engine for Cisco IOS XE Software could allow an unauthenticated, remote attacker to bypass configured security policies or cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient validation of HTTP requests when they are processed by Cisco UTD Snort IPS Engine. An attacker could exploit this vulnerability by sending a crafted HTTP request through an affected device. A successful exploit could allow the attacker to trigger a reload of the Snort process. If the action in case of Cisco UTD Snort IPS Engine failure is set to the default, fail-open, successful exploitation of this vulnerability could allow the attacker to bypass configured security policies. If the action in case of Cisco UTD Snort IPS Engine failure is set to fail-close, successful exploitation of this vulnerability could cause traffic that is configured to be inspected by Cisco UTD Snort IPS Engine to be dropped.

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CVSS v3.1 Score

5.8

MEDIUM

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

Weakness Type (CWE)

CWE-122 CWE-122

CWE-787 Out-of-bounds Write

Affected Products

Vendor	Product	Versions
cisco	unified_threat_defense_snort_intrusion_prevention_system_engine	All
cisco	unified_threat_defense_snort_intrusion_prevention_system_engine	All
cisco	unified_threat_defense_snort_intrusion_prevention_system_engine	All
cisco	unified_threat_defense_snort_intrusion_prevention_system_engine	All
cisco	unified_threat_defense_snort_intrusion_prevention_system_engine	All
cisco	unified_threat_defense_snort_intrusion_prevention_system_engine	All
cisco	unified_threat_defense_snort_intrusion_prevention_system_engine	All
cisco	unified_threat_defense_snort_intrusion_prevention_system_engine	All
cisco	unified_threat_defense_snort_intrusion_prevention_system_engine	All
cisco	unified_threat_defense_snort_intrusion_prevention_system_engine	All
cisco	unified_threat_defense_snort_intrusion_prevention_system_engine	All
cisco	unified_threat_defense_snort_intrusion_prevention_system_engine	All
cisco	unified_threat_defense_snort_intrusion_prevention_system_engine	All
cisco	unified_threat_defense_snort_intrusion_prevention_system_engine	All
cisco	unified_threat_defense_snort_intrusion_prevention_system_engine	All
cisco	unified_threat_defense_snort_intrusion_prevention_system_engine	All

References

Advisories & Patches

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-utd-snort3-dos-bypas-b4OUEwxD

Frequently Asked Questions

What is CVE-2024-20508? +

A vulnerability in Cisco Unified Threat Defense (UTD) Snort Intrusion Prevention System (IPS) Engine for Cisco IOS XE Software could allow an unauthenticated, remote attacker to bypass configured security policies or cause a denial of service (DoS) condition on an affected device. This vulnerability is due to insufficient validation of HTTP requests when they are processed by Cisco UTD Snort IPS Engine. An attacker could exploit this vulnerability by sending a crafted HTTP request through an affected device. A successful exploit could allow the attacker to trigger a reload of the Snort process. If the action in case of Cisco UTD Snort IPS Engine failure is set to the default, fail-open, successful exploitation of this vulnerability could allow the attacker to bypass configured security policies. If the action in case of Cisco UTD Snort IPS Engine failure is set to fail-close, successful exploitation of this vulnerability could cause traffic that is configured to be inspected by Cisco UTD Snort IPS Engine to be dropped. It has a CVSS v3.1 base score of 5.8 (MEDIUM).

How severe is CVE-2024-20508? +

CVE-2024-20508 has a CVSS v3.1 score of 5.8 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2024-20508? +

CVE-2024-20508 affects products from cisco, specifically: unified_threat_defense_snort_intrusion_prevention_system_engine. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-20508? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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