CVE-2019-1736: Cisco FMC1000-k9 BIOS

Medium severity, CVSS 6.6. EPSS: 0.2% chance of exploitation in the next 30 days.

A vulnerability in the firmware of the Cisco UCS C-Series Rack Servers could allow an authenticated, physical attacker to bypass Unified Extensible Firmware Interface (UEFI) Secure Boot validation checks and load a compromised software image on an affected device. The vulnerability is due to improper validation of the server firmware upgrade images. An attacker could exploit this vulnerability by installing a server firmware version that would allow the attacker to disable UEFI Secure Boot. A successful exploit could allow the attacker to bypass the signature validation checks that are done by UEFI Secure Boot technology and load a compromised software image on the affected device. A compromised software image is any software image that has not been digitally signed by Cisco.

Affected products

• Cisco FMC1000-k9 BIOS: before 4.0.1f.0 (fixed in 4.0.1f.0)
• Cisco FMC1000-k9 Firmware: before 4.0.2h (fixed in 4.0.2h)
• Cisco FMC2500-k9 BIOS: before 4.0.1f.0 (fixed in 4.0.1f.0)
• Cisco FMC2500-k9 Firmware: before 4.0.2h (fixed in 4.0.2h)
• Cisco FMC4500-k9 BIOS: before 4.0.1f.0 (fixed in 4.0.1f.0)
• Cisco FMC4500-k9 Firmware: before 4.0.2h (fixed in 4.0.2h)
• Cisco Identity Services Engine: version 2.4(0.357) only; version 2.6(0.156) only
• Cisco Sns-3515-k9 BIOS: before 4.0.2d (fixed in 4.0.2d)
• Cisco Sns-3515-k9 Firmware: before 4.0.2h (fixed in 4.0.2h)
• Cisco Sns-3595-k9 BIOS: before 4.0.2d (fixed in 4.0.2d)
• Cisco Sns-3595-k9 Firmware: before 4.0.2h (fixed in 4.0.2h)
• Cisco Sns-3615-k9 BIOS: before 4.0.1i (fixed in 4.0.1i)
• Cisco Sns-3615-k9 Firmware: before 4.0.1g (fixed in 4.0.1g)
• Cisco Sns-3655-k9 BIOS: before 4.0.1i (fixed in 4.0.1i)
• Cisco Sns-3655-k9 Firmware: before 4.0.1g (fixed in 4.0.1g)
• Cisco Sns-3695-k9 BIOS: before 4.0.1i (fixed in 4.0.1i)
• Cisco Sns-3695-k9 Firmware: before 4.0.1g (fixed in 4.0.1g)
• Cisco TG5004-k9-Rf BIOS: before 4.0.2d (fixed in 4.0.2d)
• Cisco TG5004-k9-Rf Firmware: before 4.0.2h (fixed in 4.0.2h)
• Cisco TG5004-k9 BIOS: before 4.0.2d (fixed in 4.0.2d)
• Cisco TG5004-k9 Firmware: before 4.0.2h (fixed in 4.0.2h)
• Cisco Unified Computing System: version 3.2(3h)c only

Published 2020-09-23. Last modified 2026-06-17.