CVE-2021-1223: Multiple Cisco Products Snort HTTP Detection Engine File Policy Bypass Vulnerability

Published Jan 13, 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 an HTTP range header. An attacker could exploit this vulnerability by sending crafted HTTP packets through an affected device. A successful exploit could allow the attacker to bypass configured file policy for HTTP packets and deliver a malicious payload.

Affected Software

42 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 Management Center=2.9.14.0
Cisco FirePOWER Management Center=2.9.15
Cisco FirePOWER Management Center=2.9.16
Cisco Firepower Threat Defense<6.7.0
Cisco IOS XE<17.4.1
Cisco 1100-4p Integrated Services Router
Cisco 1100-8p Integrated Services Router
Cisco 1101-4p Integrated Services Router
Cisco 1109-2p Integrated Services Router
Cisco 1109-4p Integrated Services Router
Cisco 1111x-8p Integrated Services Router
Cisco 4221 Integrated Services Router
Cisco 4321 Integrated Services Router
Cisco 4331 Integrated Services Router
Cisco 4351 Integrated Services Router
Cisco 4431 Integrated Services Router
Cisco 4451-x Integrated Services Router
Cisco 4461 Integrated Services Router
Cisco Csr 1000v
Cisco Isa 3000
Snort Snort<2.9.17
Cisco Secure Firewall Management Center=2.9.14.0
Cisco Secure Firewall Management Center=2.9.15
Cisco Secure Firewall Management Center=2.9.16
Cisco Secure Firewall Threat Defense<6.7.0
All of the following
Cisco IOS XE<17.4.1
Any of the following
Cisco 1100-4p Integrated Services Router
Cisco 1100-8p Integrated Services Router
Cisco 1101-4p Integrated Services Router
Cisco 1109-2p Integrated Services Router
Cisco 1109-4p Integrated Services Router
Cisco 1111x-8p Integrated Services Router
Cisco 4221 Integrated Services Router
Cisco 4321 Integrated Services Router
Cisco 4331 Integrated Services Router
Cisco 4351 Integrated Services Router
Cisco 4431 Integrated Services Router
Cisco 4451-x Integrated Services Router
Cisco 4461 Integrated Services Router
Cisco Csr 1000v
Cisco Isa 3000

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

Jan 13, 2021
CVE Published
via MITRE·09:16 PM
Data Sourced
via MITRE·09:16 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·10:15 PM
DescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is the vulnerability ID of this Cisco vulnerability?

The vulnerability ID of this Cisco vulnerability is CVE-2021-1223.

2

What products are affected by the CVE-2021-1223 vulnerability?

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

3

What is the severity of CVE-2021-1223?

The severity of CVE-2021-1223 is high (7.5).

4

How can an unauthenticated, remote attacker exploit CVE-2021-1223?

An unauthenticated, remote attacker can exploit CVE-2021-1223 by bypassing a configured file policy for HTTP using an incorrect HTTP range header.

5

Are there any official references for CVE-2021-1223?

Yes, there are official references available for CVE-2021-1223. You can find them at the following links:

Contact

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