BugZero | Cisco BugID CSCwi76361 - Transparent firewall MAC filter does not capture f...

background buggy image

OPERATIONAL DEFECT DATABASE

...

Operational Defect Database

A free repository of operational (non-security) bugs centralized through custom integrations with leading IT vendors.

Product

Enterprise platform
Bug Scrub Advisor
Vendor Integrations

Company

Plans
Value Guide
About
Contact us

Resources

Blog
ServiceNow App
Trust Center
Risk Management
NIST
DORA

Operational Defect Database

A free repository of operational (non-security) bugs centralized through custom integrations with leading IT vendors.

Product

Enterprise platform
Bug Scrub Advisor
Vendor Integrations

Company

Plans
Value Guide
About
Contact us

Resources

Blog
ServiceNow App
Trust Center
Risk Management
NIST
DORA

©2025 BugZero. All Rights Reserved.

Privacy Policy Terms of Service

BugZero | Cisco BugID CSCwi76361 - Transparent firewall MAC filter does not capture f...

ODD
Cisco
CSCwi76361

Cisco - Defect ID: CSCwi76361

Transparent firewall MAC filter does not capture frames with STP-UplinkFast dst MAC consistently

ODD
Cisco
CSCwi76361

Cisco - Defect ID: CSCwi76361

Transparent firewall MAC filter does not capture frames with STP-UplinkFast dst MAC consistently

Last updated on October 15th, 2025

BugZero Risk Score
6.1 Medium

Overall: 6.1

Severity: 6.4

Lifecycle: 9.1

Popularity: 4.6

What is the BugZero Risk Score?

Cisco Integration

Learn more about where this data comes from

Cisco Integration

Bug Scrub Advisor

Streamline upgrades with automated vendor bug scrubs

Bug Scrub Advisor

BugZero Enterprise

Wish you caught this bug sooner? Get proactive today.

BugZero Enterprise

Bug Details

Description

Symptom

On a firewall HA setup, in transparent mode, when using a MAC capture with a specific filter, packets are not seen all the time: capture CAP1 type raw-data interface NET100 [Capturing - 0 bytes] match mac any 0100.0ccd.cdcd ffff.ffff.ffff Trigger a failover event. You should see the Active firewall generating UplinkFast dummy packets for every MAC learned. firepower# failover active Switching to Active On the Active unit, in the captures that have the MAC filter you see nothing: firepower# show capture capture CAP1 type raw-data interface NET100 [Capturing - 0 bytes] match mac any 0100.0ccd.cdcd ffff.ffff.ffff capture CAP2 type raw-data interface NET101 [Capturing - 0 bytes] match mac any 0100.0ccd.cdcd ffff.ffff.ffff capture CAP3 type raw-data interface NET100 [Capturing - 5550 bytes] capture CAP4 type raw-data interface NET101 [Capturing - 6334 bytes] On the same unit, in the captures that do not have MAC filter, you see frames with dst MAC 0100.0ccd.cdcd: firepower# show capture CAP3 detail | i cdcd 13: 11:00:45.221210 4c4e.35fc.fcd8 0100.0ccd.cdcd 0x8100 Length: 82 14: 11:00:45.221393 c4c6.0384.6a52 0100.0ccd.cdcd 0x8100 Length: 82 15: 11:00:45.221683 0017.dfd6.ec00 0100.0ccd.cdcd 0x8100 Length: 82 On the Standby unit you see the 0100.0ccd.cdcd frames in all captures: firepower# Switching to Standby firepower# sh cap capture CAP1 type raw-data interface NET100 [Capturing - 294 bytes] match mac any 0100.0ccd.cdcd ffff.ffff.ffff capture CAP2 type raw-data interface NET101 [Capturing - 1078 bytes] match mac any 0100.0ccd.cdcd ffff.ffff.ffff capture CAP3 type raw-data interface NET100 [Capturing - 55884 bytes] capture CAP4 type raw-data interface NET101 [Capturing - 47536 bytes] firepower# show capture CAP3 det | i cdcd 474: 11:00:44.988428 4c4e.35fc.fcd8 0100.0ccd.cdcd 0x8100 Length: 82 475: 11:00:44.988581 c4c6.0384.6a52 0100.0ccd.cdcd 0x8100 Length: 82

Conditions

- Transparent FW - HA setup - Failover event - Capture with MAC filter for destination MAC 0100.0ccd.cdcd

Workaround

Further Problem Description

Change history

2025-07-09 Added: 9.10.1, 9.10.1.10, 9.10.1.11, 9.10.1.17, 9.10.1.2, 9.10.1.22, 9.10.1.27, 9.10.1.30, 9.10.1.32, 9.10.1.37, 9.10.1.40, 9.10.1.42, 9.10.1.44, 9.10.1.7, 9.12.1, 9.12.1.2, 9.12.1.3, 9.12.2, 9.12.2.1, 9.12.2.4, 9.12.2.5, 9.12.2.9, 9.12.3, 9.12.3.12, 9.12.3.2, 9.12.3.7, 9.12.3.9, 9.12.4, 9.12.4.10, 9.12.4.13, 9.12.4.18, 9.12.4.2, 9.12.4.24, 9.12.4.26, 9.12.4.29, 9.12.4.30, 9.12.4.35, 9.12.4.37, 9.12.4.38, 9.12.4.39, 9.12.4.4, 9.12.4.40, 9.12.4.41, 9.12.4.47, 9.12.4.48, 9.12.4.50, 9.12.4.52, 9.12.4.54, 9.12.4.55, 9.12.4.56, 9.12.4.58, 9.12.4.62, 9.12.4.65, 9.12.4.67, 9.12.4.7, 9.12.4.8, 9.13.1, 9.13.1.10, 9.13.1.12, 9.13.1.13, 9.13.1.16, 9.13.1.19, 9.13.1.2, 9.13.1.21, 9.13.1.7, 9.14.1, 9.14.1.10, 9.14.1.15, 9.14.1.19, 9.14.1.30, 9.14.1.6, 9.14.2, 9.14.2.13, 9.14.2.15, 9.14.2.4, 9.14.2.8, 9.14.3, 9.14.3.1, 9.14.3.11, 9.14.3.13, 9.14.3.15, 9.14.3.18, 9.14.3.9, 9.14.4, 9.14.4.12, 9.14.4.13, 9.14.4.14, 9.14.4.15, 9.14.4.17, 9.14.4.22, 9.14.4.23, 9.14.4.24, 9.14.4.6, 9.14.4.7, 9.15.1, 9.15.1.1, 9.15.1.10, 9.15.1.15, 9.15.1.16, 9.15.1.17, 9.15.1.21, 9.15.1.7, 9.16.1, 9.16.1.28, 9.16.2, 9.16.2.11, 9.16.2.13, 9.16.2.14, 9.16.2.3, 9.16.2.7, 9.16.3, 9.16.3.14, 9.16.3.15, 9.16.3.19, 9.16.3.23, 9.16.3.3, 9.16.4, 9.16.4.14, 9.16.4.18, 9.16.4.19, 9.16.4.27, 9.16.4.38, 9.16.4.39, 9.16.4.42, 9.16.4.48, 9.16.4.55, 9.16.4.9, 9.17.1, 9.17.1.10, 9.17.1.11, 9.17.1.13, 9.17.1.15, 9.17.1.20, 9.17.1.30, 9.17.1.33, 9.17.1.39, 9.17.1.45, 9.17.1.46, 9.17.1.7, 9.17.1.9, 9.18.1, 9.18.1.3, 9.18.2, 9.18.2.5, 9.18.2.7, 9.18.2.8, 9.18.3, 9.18.3.39, 9.18.3.46, 9.18.3.53, 9.18.3.55, 9.18.3.56, 9.18.4, 9.18.4.22, 9.18.4.5, 9.18.4.8, 9.19.1, 9.19.1.12, 9.19.1.18, 9.19.1.22, 9.19.1.24, 9.19.1.27, 9.19.1.28, 9.19.1.5, 9.19.1.9, 9.20.1, 9.20.1.5, 9.20.2, 9.20.2.10, 9.8.1, 9.8.1.5, 9.8.1.7, 9.8.2, 9.8.2.14, 9.8.2.15, 9.8.2.17, 9.8.2.20, 9.8.2.24, 9.8.2.26, 9.8.2.28, 9.8.2.33, 9.8.2.35, 9.8.2.38, 9.8.2.45, 9.8.2.8, 9.8.3, 9.8.3.11, 9.8.3.14, 9.8.3.16, 9.8.3.18, 9.8.3.21, 9.8.3.26, 9.8.3.29, 9.8.3.8, 9.8.4, 9.8.4.10, 9.8.4.12, 9.8.4.15, 9.8.4.17, 9.8.4.20, 9.8.4.22, 9.8.4.25, 9.8.4.26, 9.8.4.29, 9.8.4.3, 9.8.4.32, 9.8.4.33, 9.8.4.34, 9.8.4.35, 9.8.4.39, 9.8.4.40, 9.8.4.41, 9.8.4.43, 9.8.4.44, 9.8.4.45, 9.8.4.46, 9.8.4.48, 9.8.4.7, 9.8.4.8, 9.9.1, 9.9.1.2, 9.9.1.3, 9.9.1.4, 9.9.1.5, 9.9.2, 9.9.2.1, 9.9.2.14, 9.9.2.18, 9.9.2.235, 9.9.2.25, 9.9.2.27, 9.9.2.32, 9.9.2.36, 9.9.2.40, 9.9.2.47, 9.9.2.50, 9.9.2.52, 9.9.2.56, 9.9.2.59, 9.9.2.61, 9.9.2.66, 9.9.2.67, 9.9.2.74, 9.9.2.80, 9.9.2.83, 9.9.2.85, 9.9.2.9

Relevant Products

Click on a version to see all relevant bugs

Affected versions:9.10.1, 9.10.1.10, 9.10.1.11, 9.10.1.17, 9.10.1.2, 9.10.1.22, 9.10.1.27, 9.10.1.30, 9.10.1.32, 9.10.1.37, 9.10.1.40, 9.10.1.42, 9.10.1.44, 9.10.1.7, 9.12.1, 9.12.1.2, 9.12.1.3, 9.12.2, 9.12.2.1, 9.12.2.4, 9.12.2.5, 9.12.2.9, 9.12.3, 9.12.3.12, 9.12.3.2, 9.12.3.7, 9.12.3.9, 9.12.4, 9.12.4.10, 9.12.4.13, 9.12.4.18, 9.12.4.2, 9.12.4.24, 9.12.4.26, 9.12.4.29, 9.12.4.30, 9.12.4.35, 9.12.4.37, 9.12.4.38, 9.12.4.39, 9.12.4.4, 9.12.4.40, 9.12.4.41, 9.12.4.47, 9.12.4.48, 9.12.4.50, 9.12.4.52, 9.12.4.54, 9.12.4.55, 9.12.4.56, 9.12.4.58, 9.12.4.62, 9.12.4.65, 9.12.4.67, 9.12.4.7, 9.12.4.8, 9.13.1, 9.13.1.10, 9.13.1.12, 9.13.1.13, 9.13.1.16, 9.13.1.19, 9.13.1.2, 9.13.1.21, 9.13.1.7, 9.14.1, 9.14.1.10, 9.14.1.15, 9.14.1.19, 9.14.1.30, 9.14.1.6, 9.14.2, 9.14.2.13, 9.14.2.15, 9.14.2.4, 9.14.2.8, 9.14.3, 9.14.3.1, 9.14.3.11, 9.14.3.13, 9.14.3.15, 9.14.3.18, 9.14.3.9, 9.14.4, 9.14.4.12, 9.14.4.13, 9.14.4.14, 9.14.4.15, 9.14.4.17, 9.14.4.22, 9.14.4.23, 9.14.4.24, 9.14.4.6, 9.14.4.7, 9.15.1, 9.15.1.1, 9.15.1.10, 9.15.1.15, 9.15.1.16, 9.15.1.17, 9.15.1.21, 9.15.1.7, 9.16.1, 9.16.1.28, 9.16.2, 9.16.2.11, 9.16.2.13, 9.16.2.14, 9.16.2.3, 9.16.2.7, 9.16.3, 9.16.3.14, 9.16.3.15, 9.16.3.19, 9.16.3.23, 9.16.3.3, 9.16.4, 9.16.4.14, 9.16.4.18, 9.16.4.19, 9.16.4.27, 9.16.4.38, 9.16.4.39, 9.16.4.42, 9.16.4.48, 9.16.4.55, 9.16.4.9, 9.17.1, 9.17.1.10, 9.17.1.11, 9.17.1.13, 9.17.1.15, 9.17.1.20, 9.17.1.30, 9.17.1.33, 9.17.1.39, 9.17.1.45, 9.17.1.46, 9.17.1.7, 9.17.1.9, 9.18.1, 9.18.1.3, 9.18.2, 9.18.2.5, 9.18.2.7, 9.18.2.8, 9.18.3, 9.18.3.39, 9.18.3.46, 9.18.3.53, 9.18.3.55, 9.18.3.56, 9.18.4, 9.18.4.22, 9.18.4.5, 9.18.4.8, 9.19.1, 9.19.1.12, 9.19.1.18, 9.19.1.22, 9.19.1.24, 9.19.1.27, 9.19.1.28, 9.19.1.5, 9.19.1.9, 9.20.1, 9.20.1.5, 9.20.2, 9.20.2.10, 9.8.1, 9.8.1.5, 9.8.1.7, 9.8.2, 9.8.2.14, 9.8.2.15, 9.8.2.17, 9.8.2.20, 9.8.2.24, 9.8.2.26, 9.8.2.28, 9.8.2.33, 9.8.2.35, 9.8.2.38, 9.8.2.45, 9.8.2.8, 9.8.3, 9.8.3.11, 9.8.3.14, 9.8.3.16, 9.8.3.18, 9.8.3.21, 9.8.3.26, 9.8.3.29, 9.8.3.8, 9.8.4, 9.8.4.10, 9.8.4.12, 9.8.4.15, 9.8.4.17, 9.8.4.20, 9.8.4.22, 9.8.4.25, 9.8.4.26, 9.8.4.29, 9.8.4.3, 9.8.4.32, 9.8.4.33, 9.8.4.34, 9.8.4.35, 9.8.4.39, 9.8.4.40, 9.8.4.41, 9.8.4.43, 9.8.4.44, 9.8.4.45, 9.8.4.46, 9.8.4.48, 9.8.4.7, 9.8.4.8, 9.9.1, 9.9.1.2, 9.9.1.3, 9.9.1.4, 9.9.1.5, 9.9.2, 9.9.2.1, 9.9.2.14, 9.9.2.18, 9.9.2.235, 9.9.2.25, 9.9.2.27, 9.9.2.32, 9.9.2.36, 9.9.2.40, 9.9.2.47, 9.9.2.50, 9.9.2.52, 9.9.2.56, 9.9.2.59, 9.9.2.61, 9.9.2.66, 9.9.2.67, 9.9.2.74, 9.9.2.80, 9.9.2.83, 9.9.2.85, 9.9.2.9

Fixed versions: 9.16.4.57, 9.16.4.61, 9.16.4.62, 9.16.4.67, 9.16.4.70, 9.16.4.71, 9.16.4.76, 9.16.4.82, 9.16.4.84, 9.16.4.85, 9.18.4.24, 9.18.4.29, 9.18.4.34, 9.18.4.40, 9.18.4.47, 9.18.4.50, 9.18.4.52, 9.18.4.53, 9.18.4.57, 9.18.4.66, 9.18.4.67, 9.18.4.68, 9.19.1.31, 9.19.1.37, 9.19.1.38, 9.19.1.42, 9.20.2.21, 9.20.2.22, 9.20.3, 9.20.3.10, 9.20.3.13, 9.20.3.16, 9.20.3.20, 9.20.3.4, 9.20.3.7, 9.20.3.9, 9.20.4, 9.20.4.10, 9.20.4.7, 9.22.1.1, 9.22.1.2, 9.22.1.3, 9.22.1.6, 9.22.2, 9.22.2.13, 9.22.2.14, 9.22.2.4, 9.22.2.9, 9.23.1, 9.23.1.13, 9.23.1.19, 9.23.1.22, 9.23.1.3, 9.23.1.7

Relevant Products

Click on a version to see all relevant bugs

Affected versions:9.10.1, 9.10.1.10, 9.10.1.11, 9.10.1.17, 9.10.1.2, 9.10.1.22, 9.10.1.27, 9.10.1.30, 9.10.1.32, 9.10.1.37, 9.10.1.40, 9.10.1.42, 9.10.1.44, 9.10.1.7, 9.12.1, 9.12.1.2, 9.12.1.3, 9.12.2, 9.12.2.1, 9.12.2.4, 9.12.2.5, 9.12.2.9, 9.12.3, 9.12.3.12, 9.12.3.2, 9.12.3.7, 9.12.3.9, 9.12.4, 9.12.4.10, 9.12.4.13, 9.12.4.18, 9.12.4.2, 9.12.4.24, 9.12.4.26, 9.12.4.29, 9.12.4.30, 9.12.4.35, 9.12.4.37, 9.12.4.38, 9.12.4.39, 9.12.4.4, 9.12.4.40, 9.12.4.41, 9.12.4.47, 9.12.4.48, 9.12.4.50, 9.12.4.52, 9.12.4.54, 9.12.4.55, 9.12.4.56, 9.12.4.58, 9.12.4.62, 9.12.4.65, 9.12.4.67, 9.12.4.7, 9.12.4.8, 9.13.1, 9.13.1.10, 9.13.1.12, 9.13.1.13, 9.13.1.16, 9.13.1.19, 9.13.1.2, 9.13.1.21, 9.13.1.7, 9.14.1, 9.14.1.10, 9.14.1.15, 9.14.1.19, 9.14.1.30, 9.14.1.6, 9.14.2, 9.14.2.13, 9.14.2.15, 9.14.2.4, 9.14.2.8, 9.14.3, 9.14.3.1, 9.14.3.11, 9.14.3.13, 9.14.3.15, 9.14.3.18, 9.14.3.9, 9.14.4, 9.14.4.12, 9.14.4.13, 9.14.4.14, 9.14.4.15, 9.14.4.17, 9.14.4.22, 9.14.4.23, 9.14.4.24, 9.14.4.6, 9.14.4.7, 9.15.1, 9.15.1.1, 9.15.1.10, 9.15.1.15, 9.15.1.16, 9.15.1.17, 9.15.1.21, 9.15.1.7, 9.16.1, 9.16.1.28, 9.16.2, 9.16.2.11, 9.16.2.13, 9.16.2.14, 9.16.2.3, 9.16.2.7, 9.16.3, 9.16.3.14, 9.16.3.15, 9.16.3.19, 9.16.3.23, 9.16.3.3, 9.16.4, 9.16.4.14, 9.16.4.18, 9.16.4.19, 9.16.4.27, 9.16.4.38, 9.16.4.39, 9.16.4.42, 9.16.4.48, 9.16.4.55, 9.16.4.9, 9.17.1, 9.17.1.10, 9.17.1.11, 9.17.1.13, 9.17.1.15, 9.17.1.20, 9.17.1.30, 9.17.1.33, 9.17.1.39, 9.17.1.45, 9.17.1.46, 9.17.1.7, 9.17.1.9, 9.18.1, 9.18.1.3, 9.18.2, 9.18.2.5, 9.18.2.7, 9.18.2.8, 9.18.3, 9.18.3.39, 9.18.3.46, 9.18.3.53, 9.18.3.55, 9.18.3.56, 9.18.4, 9.18.4.22, 9.18.4.5, 9.18.4.8, 9.19.1, 9.19.1.12, 9.19.1.18, 9.19.1.22, 9.19.1.24, 9.19.1.27, 9.19.1.28, 9.19.1.5, 9.19.1.9, 9.20.1, 9.20.1.5, 9.20.2, 9.20.2.10, 9.8.1, 9.8.1.5, 9.8.1.7, 9.8.2, 9.8.2.14, 9.8.2.15, 9.8.2.17, 9.8.2.20, 9.8.2.24, 9.8.2.26, 9.8.2.28, 9.8.2.33, 9.8.2.35, 9.8.2.38, 9.8.2.45, 9.8.2.8, 9.8.3, 9.8.3.11, 9.8.3.14, 9.8.3.16, 9.8.3.18, 9.8.3.21, 9.8.3.26, 9.8.3.29, 9.8.3.8, 9.8.4, 9.8.4.10, 9.8.4.12, 9.8.4.15, 9.8.4.17, 9.8.4.20, 9.8.4.22, 9.8.4.25, 9.8.4.26, 9.8.4.29, 9.8.4.3, 9.8.4.32, 9.8.4.33, 9.8.4.34, 9.8.4.35, 9.8.4.39, 9.8.4.40, 9.8.4.41, 9.8.4.43, 9.8.4.44, 9.8.4.45, 9.8.4.46, 9.8.4.48, 9.8.4.7, 9.8.4.8, 9.9.1, 9.9.1.2, 9.9.1.3, 9.9.1.4, 9.9.1.5, 9.9.2, 9.9.2.1, 9.9.2.14, 9.9.2.18, 9.9.2.235, 9.9.2.25, 9.9.2.27, 9.9.2.32, 9.9.2.36, 9.9.2.40, 9.9.2.47, 9.9.2.50, 9.9.2.52, 9.9.2.56, 9.9.2.59, 9.9.2.61, 9.9.2.66, 9.9.2.67, 9.9.2.74, 9.9.2.80, 9.9.2.83, 9.9.2.85, 9.9.2.9

Fixed versions: 9.16.4.57, 9.16.4.61, 9.16.4.62, 9.16.4.67, 9.16.4.70, 9.16.4.71, 9.16.4.76, 9.16.4.82, 9.16.4.84, 9.16.4.85, 9.18.4.24, 9.18.4.29, 9.18.4.34, 9.18.4.40, 9.18.4.47, 9.18.4.50, 9.18.4.52, 9.18.4.53, 9.18.4.57, 9.18.4.66, 9.18.4.67, 9.18.4.68, 9.19.1.31, 9.19.1.37, 9.19.1.38, 9.19.1.42, 9.20.2.21, 9.20.2.22, 9.20.3, 9.20.3.10, 9.20.3.13, 9.20.3.16, 9.20.3.20, 9.20.3.4, 9.20.3.7, 9.20.3.9, 9.20.4, 9.20.4.10, 9.20.4.7, 9.22.1.1, 9.22.1.2, 9.22.1.3, 9.22.1.6, 9.22.2, 9.22.2.13, 9.22.2.14, 9.22.2.4, 9.22.2.9, 9.23.1, 9.23.1.13, 9.23.1.19, 9.23.1.22, 9.23.1.3, 9.23.1.7

Top Cisco Defects

9.7Defect ID: CSCuz46500
Fib_mgr process crash due to "not enough memory"
9.7Defect ID: CSCwe01579
Cat9800 wncd reload while creating an RRM Client Coverage on large scale setup
9.7Defect ID: CSCwa47133
ISE Evaluation log4j CVE-2021-44228
9.7Defect ID: CSCwa47745
Evaluation of vmanage for Log4j RCE (Log4Shell) Vulnerability vulnerability
9.7Defect ID: CSCwa00729
All NADs got deleted due to one particular NAD deletion

Ready to prevent the next vendor outage?

Links

Original Vendor Announcement

Cisco Integration

Learn more about where this data comes from

Cisco Integration

Bug Scrub Advisor

Streamline upgrades with automated vendor bug scrubs

Bug Scrub Advisor

BugZero Enterprise

Wish you caught this bug sooner? Get proactive today.

BugZero Enterprise