- #Cisco ios xe software serial
- #Cisco ios xe software Patch
- #Cisco ios xe software verification
- #Cisco ios xe software software
This vulnerability affects Cisco products with an FPGA based TAm. The vulnerability was demonstrated on a Cisco ASR 1001-X router. On what device(s) did you demonstrate the vulnerability?
#Cisco ios xe software software
It is also possible to lock out any software updates to the TAm’s bitstream. Successful modification of the bitstream is persistent, and the Trust Anchor will be disabled in Elements of this bitstream can be modified to disable critical functionality What is the vulnerability in Cisco’s Trust Anchor?Īn attacker with root privileges on the device can modify the contents of the FPGA anchor bitstream, which If the FPGA anchor detects any integrity violations in the pre-boot environment, The FPGA anchor is connected to the main processor via its south bridge and controls
#Cisco ios xe software verification
The FPGA performs integrity verification of the pre-boot environment, before the microloader is delivered
#Cisco ios xe software serial
The FPGA loads an unencrypted bitstream implementing the hardware Trust Anchor to provide root of trustįunctionality from a dedicated Serial Peripheral Interface (SPI) flash chip. How is Cisco’s Trust Anchor implemented?Īt the design level, the hardware anchor is implemented using an external FPGA. Preventing the device from executing the modified bootloader. Should any failure be detected, the device alerts the user and reboots the device, thus After system power-on, the TAm runs the first instructions, which immediately verify the integrity Special-purpose hardware device, known as the Trust Anchor module (TAm), as a root of trust for the secureīoot process. To perform this validation each time the device resets, Cisco developed a separate,
#Cisco ios xe software Patch
Since the flaws reside within the hardware design, it is unlikely that any software security patch willįully resolve the fundamental security vulnerability.Ĭisco Secure Boot is a secure startup process that ensures the integrity of the firmware running onĬisco hardware devices. While the flaws are based in hardware, ??? can be exploited remotely without any need for Trust Anchor module via FPGA bitstream modification, thereby defeating the secure boot process and invalidating Cisco’sĬhain of trust at its root. ??? allows an attacker to make persistent modification to the TAm is the root of trust that underpins all other Cisco securityĪnd trustworthy computing mechanisms in these devices. Including enterprise routers, switches and firewalls. First commercially introduced inĢ013, Cisco Trust Anchor module (TAm) is a proprietary hardware security module used in a wide range of Cisco products, ??? is caused by a series of hardware design flaws within Cisco’s Trust Anchor module. By chaining the ??? and remote command injection vulnerabilities, an attacker can remotelyĪnd persistently bypass Cisco’s secure boot mechanism and lock out all future software updates to the TAm. The second is a remote command injection vulnerability against Cisco IOS XE version 16 that allows The first, known as ???, allows an attacker to fully bypass Cisco’s Trust Anchor module (TAm) via Field Programmable Gate Array is disclosing two vulnerabilities affecting the products of Cisco Systems, Inc. We are excited to announce that ??? has won the 2019 Pwnie Award for the Most Under-Hyped Research! The visualization file is generated by the BAL framework, and the visualization application runs entirely in a browser and no data is uploaded to the network. Lastly, we developed the BAL Visualizer which is a tool used to visualize binary data. (i) packing and unpacking of most of the bitstream (ii) target device and encryption detection and (iii) pin modification (force the pin high and low). Second, we developed a BAL Xilinx package, an implementation of the BAL framework for Xilinx FPGA. The presentation, titled “100 Seconds of Solitude: Defeating Cisco Trust Anchor With FPGA Bitstream Shenanigans",įollowing Black Hat 2019 and DEF CON 27, we released open-source tools which are available on Github.įirst, we developed a Binary Abstraction Layer (BAL) package which is a tiny framework for analyzing and manipulating binary data. This research was presented at Black Hat 2019 and DEF CON 27.