Cisco Open Source Snort HTTP Intrusion Prevention System Rule authentication spoofing

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.4$0-$5k0.00

Summaryinfo

A vulnerability was found in Cisco Open Source Snort, FirePOWER, Firepower Threat Defense Software and IOS XE. It has been classified as critical. This affects an unknown part of the component HTTP Intrusion Prevention System Rule. The manipulation leads to authentication spoofing. This vulnerability is traded as CVE-2024-20363. It is possible to initiate the attack remotely. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Cisco Open Source Snort, FirePOWER, Firepower Threat Defense Software and IOS XE (unknown version). It has been rated as critical. This issue affects an unknown code block of the component HTTP Intrusion Prevention System Rule. The manipulation with an unknown input leads to a authentication spoofing vulnerability. Using CWE to declare the problem leads to CWE-290. This attack-focused weakness is caused by incorrectly implemented authentication schemes that are subject to spoofing attacks. Impacted is integrity. The summary by CVE is:

Multiple Cisco products are affected by a vulnerability in the Snort Intrusion Prevention System (IPS) rule engine that could allow an unauthenticated, remote attacker to bypass the configured rules on an affected system. This vulnerability is due to incorrect HTTP packet handling. 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 IPS rules and allow uninspected traffic onto the network.

The advisory is shared at sec.cloudapps.cisco.com. The identification of this vulnerability is CVE-2024-20363 since 11/08/2023. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 07/03/2025).

Upgrading eliminates this vulnerability.

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Productinfo

Type

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.4

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 5.8
CNA Vector: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Authentication spoofing
CWE: CWE-290 / CWE-287
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

11/08/2023 🔍
05/22/2024 +195 days 🔍
05/22/2024 +0 days 🔍
07/03/2025 +407 days 🔍

Sourcesinfo

Vendor: cisco.com

Advisory: cisco-sa-snort3-ips-bypass-uE69KBMd
Status: Confirmed

CVE: CVE-2024-20363 (🔍)
GCVE (CVE): GCVE-0-2024-20363
GCVE (VulDB): GCVE-100-265949
scip Labs: https://www.scip.ch/en/?labs.20150108

Entryinfo

Created: 05/22/2024 18:50
Updated: 07/03/2025 19:25
Changes: 05/22/2024 18:50 (53), 07/03/2025 19:25 (14)
Complete: 🔍
Cache ID: 216::103

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