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TI-2021-00951 Aliases CVE-2021-1224GHSA-p854-c355-26cj

Multiple Cisco Products Snort TCP Fast Open File Policy Bypass Vulnerability

Priority LOW 36CWE-693Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
None · Low · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-693.

Summary

Multiple Cisco products are affected by a vulnerability with TCP Fast Open (TFO) when used in conjunction with 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 the HTTP payload if it is contained at least partially within the TFO connection handshake. An attacker could exploit this vulnerability by sending crafted TFO packets with an HTTP payload through an affected device. A successful exploit could allow the attacker to bypass configured file policy for HTTP packets and deliver a malicious payload.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.02046 81st percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
CiscoCisco Firepower Threat Defense Softwareall versions—No fix listedCNA
  • Cisco Firepower Threat Defense Software VendorCisco Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 48

CPEVersionsRoleVendor
cpe:2.3:a:cisco:secure_firewall_management_center:2.9.14.0:*:*:*:*:*:*:*2.9.14.0VulnerableCisco
cpe:2.3:a:cisco:secure_firewall_management_center:2.9.15:*:*:*:*:*:*:*2.9.15VulnerableCisco
cpe:2.3:a:cisco:secure_firewall_management_center:2.9.16:*:*:*:*:*:*:*2.9.16VulnerableCisco
cpe:2.3:a:cisco:secure_firewall_management_center:2.9.17:*:*:*:*:*:*:*2.9.17VulnerableCisco
cpe:2.3:a:cisco:secure_firewall_management_center:2.9.18:*:*:*:*:*:*:*2.9.18VulnerableCisco
cpe:2.3:a:cisco:secure_firewall_management_center:3.0.1:*:*:*:*:*:*:*3.0.1VulnerableCisco
cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:*before 6.7.0VulnerableCisco
cpe:2.3:o:cisco:ios_xe:*:*:*:*:*:*:*:*before 17.4.1VulnerableCisco
cpe:2.3:h:cisco:1100-4p_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:1100-8p_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
  • cpe:2.3:a:cisco:secure_firewall_management_center:2.9.14.0:*:*:*:*:*:*:* Versions 2.9.14.0 Vulnerable ·Cisco
  • cpe:2.3:a:cisco:secure_firewall_management_center:2.9.15:*:*:*:*:*:*:* Versions 2.9.15 Vulnerable ·Cisco
  • cpe:2.3:a:cisco:secure_firewall_management_center:2.9.16:*:*:*:*:*:*:* Versions 2.9.16 Vulnerable ·Cisco
  • cpe:2.3:a:cisco:secure_firewall_management_center:2.9.17:*:*:*:*:*:*:* Versions 2.9.17 Vulnerable ·Cisco
  • cpe:2.3:a:cisco:secure_firewall_management_center:2.9.18:*:*:*:*:*:*:* Versions 2.9.18 Vulnerable ·Cisco
  • cpe:2.3:a:cisco:secure_firewall_management_center:3.0.1:*:*:*:*:*:*:* Versions 3.0.1 Vulnerable ·Cisco
  • cpe:2.3:a:cisco:secure_firewall_threat_defense:*:*:*:*:*:*:*:* Versions before 6.7.0 Vulnerable ·Cisco
  • cpe:2.3:o:cisco:ios_xe:*:*:*:*:*:*:*:* Versions before 17.4.1 Vulnerable ·Cisco
  • cpe:2.3:h:cisco:1100-4p_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:1100-8p_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
Show 38 more CPE
CPEVersionsRoleVendor
cpe:2.3:h:cisco:1101-4p_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:1109-2p_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:1109-4p_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:1111x-8p_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:4221_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:4321_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:4331_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:4351_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:4431_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:4451-x_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:4461_integrated_services_router:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:csr_1000v:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:h:cisco:isa_3000:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:a:snort:snort:*:*:*:*:*:*:*:*before 2.9.17VulnerableSnort
cpe:2.3:o:cisco:meraki_mx64_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableCisco
cpe:2.3:h:cisco:meraki_mx64:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:meraki_mx64w_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableCisco
cpe:2.3:h:cisco:meraki_mx64w:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:meraki_mx67_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableCisco
cpe:2.3:h:cisco:meraki_mx67:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:meraki_mx67c_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableCisco
cpe:2.3:h:cisco:meraki_mx67c:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:meraki_mx67w_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableCisco
cpe:2.3:h:cisco:meraki_mx67w:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:meraki_mx68_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableCisco
cpe:2.3:h:cisco:meraki_mx68:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:meraki_mx68cw_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableCisco
cpe:2.3:h:cisco:meraki_mx68cw:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:meraki_mx68w_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableCisco
cpe:2.3:h:cisco:meraki_mx68w:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:meraki_mx100_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableCisco
cpe:2.3:h:cisco:meraki_mx100:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:meraki_mx84_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableCisco
cpe:2.3:h:cisco:meraki_mx84:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:meraki_mx250_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableCisco
cpe:2.3:h:cisco:meraki_mx250:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
cpe:2.3:o:cisco:meraki_mx450_firmware:-:*:*:*:*:*:*:*not specified by NVDVulnerableCisco
cpe:2.3:h:cisco:meraki_mx450:-:*:*:*:*:*:*:*not specified by NVDRunning onCisco
  • cpe:2.3:h:cisco:1101-4p_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:1109-2p_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:1109-4p_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:1111x-8p_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:4221_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:4321_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:4331_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:4351_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:4431_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:4451-x_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:4461_integrated_services_router:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:csr_1000v:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:h:cisco:isa_3000:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:a:snort:snort:*:*:*:*:*:*:*:* Versions before 2.9.17 Vulnerable ·Snort
  • cpe:2.3:o:cisco:meraki_mx64_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Cisco
  • cpe:2.3:h:cisco:meraki_mx64:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:o:cisco:meraki_mx64w_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Cisco
  • cpe:2.3:h:cisco:meraki_mx64w:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:o:cisco:meraki_mx67_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Cisco
  • cpe:2.3:h:cisco:meraki_mx67:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:o:cisco:meraki_mx67c_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Cisco
  • cpe:2.3:h:cisco:meraki_mx67c:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:o:cisco:meraki_mx67w_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Cisco
  • cpe:2.3:h:cisco:meraki_mx67w:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:o:cisco:meraki_mx68_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Cisco
  • cpe:2.3:h:cisco:meraki_mx68:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:o:cisco:meraki_mx68cw_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Cisco
  • cpe:2.3:h:cisco:meraki_mx68cw:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:o:cisco:meraki_mx68w_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Cisco
  • cpe:2.3:h:cisco:meraki_mx68w:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:o:cisco:meraki_mx100_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Cisco
  • cpe:2.3:h:cisco:meraki_mx100:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:o:cisco:meraki_mx84_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Cisco
  • cpe:2.3:h:cisco:meraki_mx84:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:o:cisco:meraki_mx250_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Cisco
  • cpe:2.3:h:cisco:meraki_mx250:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco
  • cpe:2.3:o:cisco:meraki_mx450_firmware:-:*:*:*:*:*:*:* Versions not specified by NVD Vulnerable ·Cisco
  • cpe:2.3:h:cisco:meraki_mx450:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Cisco

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-1224
  2. 2026-10-03 Alias added: GHSA-p854-c355-26cj

References

  • TI-2023-06904 Cisco is providing an update for the ongoing investigation into observed exploitation of… KEVCVSS 3.1CRITICAL 10.0
  • TI-2018-00122 Memory corruption in Cisco IOS and IOS XE KEVCVSS 3.1CRITICAL 9.8
  • TI-2017-02977 Improper input validation in Cisco IOS and IOS XE Software KEVCVSS 3.1CRITICAL 9.8
  • TI-2018-00135 Memory corruption in Cisco IOS, IOS XE, and IOS XR KEVCVSS 3.1HIGH 8.8
  • TI-2017-04498 Memory corruption in Cisco IOS KEVCVSS 3.1HIGH 8.8
  • TI-2017-04497 Memory corruption in Cisco IOS XE Software KEVCVSS 3.1HIGH 8.8
See all 561 →

Sources