CVE-2020-3299

mediumpriority · track · 24EPSS 0.023 · 83 %ileDEEURUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
2.31% (83rd) EPSS
CVSS 5 · medium
Is it mine?
101 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-26

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 detection of modified HTTP packets used in chunked responses. 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.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

  • FixedCisco 4000 Series Integrated Services Routerscisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3 when installed on Cisco Firepower 2100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3 when installed on Cisco Firepower 4100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3 when installed on Cisco Firepower 9000 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.1 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.1 when installed on Cisco Firepower 2100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.1 when installed on Cisco Firepower 4100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.1 when installed on Cisco Firepower 9000 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.1 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.10 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.10 when installed on Cisco Firepower 2100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.10 when installed on Cisco Firepower 4100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.10 when installed on Cisco Firepower 9000 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.10 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.11 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.11 when installed on Cisco Firepower 2100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.11 when installed on Cisco Firepower 4100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.11 when installed on Cisco Firepower 9000 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.11 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.12 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.12 when installed on Cisco Firepower 2100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.12 when installed on Cisco Firepower 4100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.12 when installed on Cisco Firepower 9000 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.12 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.13 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.13 when installed on Cisco Firepower 2100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.13 when installed on Cisco Firepower 4100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.13 when installed on Cisco Firepower 9000 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.13 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.14 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.14 when installed on Cisco Firepower 2100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.14 when installed on Cisco Firepower 4100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.14 when installed on Cisco Firepower 9000 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.14 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.15 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.15 when installed on Cisco Firepower 2100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.15 when installed on Cisco Firepower 4100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.15 when installed on Cisco Firepower 9000 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.15 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.16 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.16 when installed on Cisco Firepower 2100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.16 when installed on Cisco Firepower 4100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.16 when installed on Cisco Firepower 9000 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.16 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.2 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.2 when installed on Cisco Firepower 2100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.2 when installed on Cisco Firepower 4100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.2 when installed on Cisco Firepower 9000 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.2 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.3 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.3 when installed on Cisco Firepower 2100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.3 when installed on Cisco Firepower 4100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.3 when installed on Cisco Firepower 9000 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.3 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.4 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.4 when installed on Cisco Firepower 2100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.4 when installed on Cisco Firepower 4100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.4 when installed on Cisco Firepower 9000 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.4 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.5 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.5 when installed on Cisco Firepower 2100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.5 when installed on Cisco Firepower 4100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.5 when installed on Cisco Firepower 9000 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.5 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.6 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.6 when installed on Cisco Firepower 2100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.6 when installed on Cisco Firepower 4100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.6 when installed on Cisco Firepower 9000 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.6 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.7 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.7 when installed on Cisco Firepower 2100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.7 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.8 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.8 when installed on Cisco Firepower 2100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.8 when installed on Cisco Firepower 4100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.8 when installed on Cisco Firepower 9000 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.8 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.9 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.9 when installed on Cisco Firepower 2100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.9 when installed on Cisco Firepower 4100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.9 when installed on Cisco Firepower 9000 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.2.3.9 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco UTD SNORT IPS Engine Softwarecisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
02

cvss

Technical severity, 0–10. One row per scoring source.

5.8
010

base score 0–10 · higher = more severe · hover a vector to decode

v2.05mediumAV:N/AC:L/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 10 · impact 2.9
v3.15.8mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 1.4
v3.05.8mediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:Nsecondary · ENISA EU
v3.05.8mediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:Nsecondary · psirt@cisco.com USexploitability 3.9 · impact 1.4
v3.05.8mediumCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:Nsecondary · Cisco PSIRT US
v3.15.8mediumAV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:Nsecondary · FSTEC (BDU) RU
v3.15.3mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-693USCWE-693US
05

affected products (101)

Products and version ranges known to be affected.

showing 20 of 101
06

advisories (2)

Vendor and ecosystem advisories describing this.

  • WID-SEC-W-2023-0340Verschiedene Cisco Produkte: Schwachstelle ermöglicht Umgehen von SicherheitsvorkehrungenDeutsch2020-10-21csaf · cert_bundDE

    Ein entfernter, anonymer Angreifer kann eine Schwachstelle in der Snort Detection Engine in verschiedenen Cisco Produkten ausnutzen, um Sicherheitsvorkehrungen zu umgehen.

  • cisco-sa-ftd-bypass-3eCfd24jMultiple Cisco Products SNORT HTTP Detection Engine File Policy Bypass Vulnerability2020-10-21csaf · cisco_csafUS

    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 detection of modified HTTP packets used in chunked responses. 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. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

07

also known as (4)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducert_bundcisco_csafNVDCVE.orgMITRE
published 2020-10-21modified 2026-08-11
09

references (15)

External citations — patches, advisories, analysis.

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