Intro

do you wanna login into your cisco switches with ssh & public key. you can build your config easily and copy/paste it to your switch(es).

Set & Check Variables

• pubkey: read from ~/.ssh/id_rsa.pub
• username: root
• password: will be generated. or set it by hand

# get & convert public key
pubkey=$(cat ~/.ssh/id_rsa.pub |cut -d' ' -f 2 |fold -b -w 72)

# Username Switch
username=root

# Password for User
password=$(openssl rand -hex 12)

# Full Line
echo "username $username privilege 15 password $password"

SSH Pubkey Auth Config Snippet

# Build Config
cat  << EOF


############################################
# Copy/Paste to your Cisco Devices - START #
############################################

conf t

# Set Version
ip ssh version 2
no aaa new-model

# Set User
username $username privilege 15 password $password

# Set Key
ip ssh pubkey-chain 
username $username 
key-string
$pubkey
exit
exit
exit

# vty Stuff
line vty 0 15
 login local
 transport input ssh

end
write
exit

############################################
# Copy/Paste to your Cisco Devices - END   #
############################################


EOF

you should test it in a lab environment before running on productiv switches ;)

Intro

I stumbled across an old Cisco box in the basement. I thought i might have some fun (or frust?) with the aging Device. The Hardware still works fine, right ? And what about the Software ? Let’s give a try !

Hardware

show version

Cisco 1841 (revision 7.0) with 352256K/40960K bytes of memory.
Processor board ID FCZ1234757Y
6 FastEthernet interfaces
1 Virtual Private Network (VPN) Module
DRAM configuration is 64 bits wide with parity disabled.
191K bytes of NVRAM.
125184K bytes of ATA CompactFlash (Read/Write)

Configuration register is 0x2102

Software

dir flash

Security posture via Cisco PSIRT OpenVuln API

Platform: iosxe

Version: 03.06.04.E

sha256: 6ab81f9b045a4de2e9b66ef802fe94d2210aa108290fb0c849696f5a7e99eac4

Security posture via Cisco PSIRT OpenVuln API

Platform: iosxe

Version: 03.08.06.E

sha256: 197718c2b28d9ab55520a09e39a603e394e0401dea6a94a3752eeb18bec4f18a

Security posture via Cisco PSIRT OpenVuln API

Platform: iosxe

Version: 17.01.01

sha256: 7ddd18e78e70dc6896588bffe741600078f06f5fe0bb7a55aa1fabb5979528b9

Security posture via Cisco PSIRT OpenVuln API

Platform: ios

Version: 15.4(1)SY4

sha256: c3e4b89e9a31fa5a69fa1ff4839762a32c00430cb927caaf267501554832ac61

Security posture via Cisco PSIRT OpenVuln API

Platform: ios

Version: 15.2(1)SY5

sha256: bce3f1e18d4915a7635960f328d32af63e5d8aa804d1e1105dcea0da79e1b5e0

Security posture via Cisco PSIRT OpenVuln API

Platform: nxos

Version: 8.2(4)

sha256: 83f05371aa9a76dc79231c5794783649ccf885061887a5d55bc0d7b2d9ad4fb7

Security posture via Cisco PSIRT OpenVuln API

Platform: iosxe

Version: 03.08.09.E

sha256: 397e05c88b687a24a6437aef9e0a3eb7a0ffc1b7041065b122ebc5a9c2b85aaf

Security posture via Cisco PSIRT OpenVuln API

Platform: ios

Version: 15.0(2)SE8

sha256: 79bf0448ec96592b255cae56173d8046be1d26090c12f05c8ec949a5e494e8f4