CVE-2021-1495: Multiple Cisco Products Snort HTTP Detection Engine File Policy Bypass Vulnerability

Published Apr 29, 2021
·
Updated

Multiple Cisco products are affected by a vulnerability in the Snort detection engine that could allow an unauthenticated, remote attacker to bypass a configured file policy for HTTP. The vulnerability is due to incorrect handling of specific HTTP header parameters. An attacker could exploit this vulnerability by sending crafted HTTP packets through an affected device. A successful exploit could allow the attacker to bypass a configured file policy for HTTP packets and deliver a malicious payload.

Affected Software

53 affected componentsFixes available
debian/snort<=2.9.7.0-5, <=2.9.15.1-5, <=2.9.15.1-6
2.9.20-0+deb10u12.9.20-0+deb11u1
Cisco Firepower Threat Defense<6.4.0.12
Cisco Firepower Threat Defense>=6.5.0<6.6.4
Cisco Firepower Threat Defense>=6.7.0<6.7.0.2
Cisco IOS XE>=16.12<16.12.5
Snort Snort<2.9.17.1
Cisco IOS XE>=17.1<17.3.3
Cisco IOS XE>=17.4<17.4.1
Cisco 1100-4g\/6g Integrated Services Router
Cisco 1101 Integrated Services Router
Cisco 1109 Integrated Services Router
Cisco 1111x Integrated Services Router
Cisco 111x Integrated Services Router
Cisco 1120 Integrated Services Router
Cisco 1160 Integrated Services Router
Cisco 3000 Integrated Services Router
Cisco 4221 Integrated Services Router
Cisco 4331 Integrated Services Router
Cisco 4431 Integrated Services Router
Cisco 4461 Integrated Services Router
Cisco C8200-1n-4t
Cisco C8200l-1n-4t
Cisco Catalyst 8300-1n1s-4t2x
Cisco Catalyst 8300-1n1s-6t
Cisco Catalyst 8300-2n2s-4t2x
Cisco Catalyst 8300-2n2s-6t
Cisco Catalyst 8500l
Cisco Secure Firewall Threat Defense<6.4.0.12
Cisco Secure Firewall Threat Defense>=6.5.0<6.6.4
Cisco Secure Firewall Threat Defense>=6.7.0<6.7.0.2
All of the following
Any of the following
Cisco IOS XE>=16.12<16.12.5
Snort Snort<2.9.17.1
Cisco IOS XE>=17.1<17.3.3
Cisco IOS XE>=17.4<17.4.1
Any of the following
Cisco 1100-4g\/6g Integrated Services Router
Cisco 1101 Integrated Services Router
Cisco 1109 Integrated Services Router
Cisco 1111x Integrated Services Router
Cisco 111x Integrated Services Router
Cisco 1120 Integrated Services Router
Cisco 1160 Integrated Services Router
Cisco 3000 Integrated Services Router
Cisco 4221 Integrated Services Router
Cisco 4331 Integrated Services Router
Cisco 4431 Integrated Services Router
Cisco 4461 Integrated Services Router
Cisco C8200-1n-4t
Cisco C8200l-1n-4t
Cisco Catalyst 8300-1n1s-4t2x
Cisco Catalyst 8300-1n1s-6t
Cisco Catalyst 8300-2n2s-4t2x
Cisco Catalyst 8300-2n2s-6t
Cisco Catalyst 8500l

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade debian/snort to a version that resolves this vulnerability.

    Fixed in 2.9.20-0+deb10u1Fixed in 2.9.20-0+deb11u1

Event History

Apr 29, 2021
CVE Published
via MITRE·05:31 PM
Data Sourced
via MITRE·05:31 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·06:15 PM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the vulnerability ID for this vulnerability?

The vulnerability ID for this vulnerability is CVE-2021-1495.

2

Which Cisco products are affected by this vulnerability?

Multiple Cisco products are affected, including Cisco Firepower Threat Defense and Cisco IOS XE.

3

What is the severity of CVE-2021-1495?

The severity of CVE-2021-1495 is medium with a CVSS score of 5.3.

4

How can an attacker exploit CVE-2021-1495?

An attacker can exploit CVE-2021-1495 by bypassing a configured file policy for HTTP.

5

What is the recommended solution for CVE-2021-1495?

The recommended solution for CVE-2021-1495 is to update to the latest version of the affected software.

Contact

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