CVE-2021-1236

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Summary

CVECVE-2021-1236
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-01-13 22:15:00 UTC
Updated2023-05-22 18:57:00 UTC
DescriptionMultiple Cisco products are affected by a vulnerability in the Snort application detection engine that could allow an unauthenticated, remote attacker to bypass the configured policies on an affected system. The vulnerability is due to a flaw in the detection algorithm. An attacker could exploit this vulnerability by sending crafted packets that would flow through an affected system. A successful exploit could allow the attacker to bypass the configured policies and deliver a malicious payload to the protected network.

Risk And Classification

Problem Types: CWE-670

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Hardware Cisco 1100-4p Integrated Services Router - All All All
Hardware Cisco 1100-8p Integrated Services Router - All All All
Hardware Cisco 1101-4p Integrated Services Router - All All All
Hardware Cisco 1109-2p Integrated Services Router - All All All
Hardware Cisco 1109-4p Integrated Services Router - All All All
Hardware Cisco 1111x-8p Integrated Services Router - All All All
Hardware Cisco 4221 Integrated Services Router - All All All
Hardware Cisco 4321 Integrated Services Router - All All All
Hardware Cisco 4331 Integrated Services Router - All All All
Hardware Cisco 4351 Integrated Services Router - All All All
Hardware Cisco 4431 Integrated Services Router - All All All
Hardware Cisco 4451-x Integrated Services Router - All All All
Hardware Cisco 4461 Integrated Services Router - All All All
Hardware Cisco Csr 1000v - All All All
Hardware Cisco Csr 1000v - All All All
Hardware Cisco Csr 1000v - All All All
Application Cisco Firepower Management Center 2.9.14.0 All All All
Application Cisco Firepower Management Center 2.9.14.14 All All All
Application Cisco Firepower Management Center 2.9.15 All All All
Application Cisco Firepower Management Center 2.9.16 All All All
Application Cisco Firepower Management Center 2.9.17 All All All
Application Cisco Firepower Management Center 2.9.14.0 All All All
Application Cisco Firepower Management Center 2.9.14.14 All All All
Application Cisco Firepower Management Center 2.9.15 All All All
Application Cisco Firepower Management Center 2.9.16 All All All
Application Cisco Firepower Management Center 2.9.17 All All All
Application Cisco Firepower Threat Defense All All All All
Application Cisco Firepower Threat Defense All All All All
Operating System Cisco Ios Xe All All All All
Operating System Cisco Ios Xe All All All All
Hardware Cisco Isa 3000 - All All All
Hardware Cisco Isa 3000 - All All All
Hardware Cisco Isa 3000 - All All All
Hardware Cisco Isr 1100-4p - All All All
Hardware Cisco Isr 1100-4p - All All All
Hardware Cisco Isr 1100-4p - All All All
Hardware Cisco Isr 1100-8p - All All All
Hardware Cisco Isr 1100-8p - All All All
Hardware Cisco Isr 1100-8p - All All All
Hardware Cisco Isr 1101-4p - All All All
Hardware Cisco Isr 1101-4p - All All All
Hardware Cisco Isr 1101-4p - All All All
Hardware Cisco Isr 1109-2p - All All All
Hardware Cisco Isr 1109-2p - All All All
Hardware Cisco Isr 1109-2p - All All All
Hardware Cisco Isr 1109-4p - All All All
Hardware Cisco Isr 1109-4p - All All All
Hardware Cisco Isr 1109-4p - All All All
Hardware Cisco Isr 1111x-8p - All All All
Hardware Cisco Isr 1111x-8p - All All All
Hardware Cisco Isr 1111x-8p - All All All
Hardware Cisco Isr 4221 - All All All
Hardware Cisco Isr 4221 - All All All
Hardware Cisco Isr 4221 - All All All
Hardware Cisco Isr 4321 - All All All
Hardware Cisco Isr 4321 - All All All
Hardware Cisco Isr 4321 - All All All
Hardware Cisco Isr 4331 - All All All
Hardware Cisco Isr 4331 - All All All
Hardware Cisco Isr 4331 - All All All
Hardware Cisco Isr 4351 - All All All
Hardware Cisco Isr 4351 - All All All
Hardware Cisco Isr 4351 - All All All
Hardware Cisco Isr 4431 - All All All
Hardware Cisco Isr 4431 - All All All
Hardware Cisco Isr 4431 - All All All
Hardware Cisco Isr 4451-x - All All All
Hardware Cisco Isr 4451-x - All All All
Hardware Cisco Isr 4451-x - All All All
Hardware Cisco Isr 4461 - All All All
Hardware Cisco Isr 4461 - All All All
Hardware Cisco Isr 4461 - All All All
Application Snort Snort All All All All
Application Snort Snort All All All All

References

ReferenceSourceLinkTags
Multiple Cisco Products Snort Application Detection Engine Policy Bypass Vulnerability CISCO tools.cisco.com Vendor Advisory
Debian -- Security Information -- DSA-5354-1 snort DEBIAN www.debian.org
[SECURITY] [DLA 3317-1] snort security update MLIST lists.debian.org
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Legacy QID Mappings

  • 179407 Debian Security Update for snort (CVE-2021-1236)
  • 181554 Debian Security Update for snort (DLA 3317-1)
  • 181678 Debian Security Update for snort (DSA 5354-1)
  • 317250 Multiple Cisco Products Snort Application Detection Engine Policy Bypass Vulnerability (cisco-sa-snort-app-bypass-cSBYCATq)
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