In investigating issues with users on GlobalProtect VPN not being able to connect to Citrix VDA servers I bumped into this forum post. In investigating I first disabled the Packet Based Attack Protection > IP Drop > Fragmented traffic at Network > Network Profiles > Zone Protection > Profiles for GlobalProtect and the zone hosting the Citrix application. While this… Read more
CITC 2024 Practical steps to help mitigate the risk of Zero-Day vulnerabilities
Something new for this year’s presentation at CITC, instead of your classic PowerPoint slides I’ve produced a GitHub repo with the intent on building out the knowledge and ideas presented overtime. GitHub repo: https://github.com/jamesfed/0DayMitigations/
Microsoft Remote Desktop connection – ‘An internal error has occurred’ and ‘The server security layer detected an error (0x80090304)’ event ID 139.
An interesting issue that was discovered after deploying security certificates for Remote Desktop Authentication into the TPM of desktop computers and some (physical) servers, after go live with the security certificate clients could no longer connect with the error below being displayed in the Remote Desktop Services log on the server. The server security layer detected an error (0x80090304) in… Read more
SNMPv3 on Dell OS 10 switches
After how woefully lacking in detail for the novice in OS 10 switches the Dell documentation is below is a little snippet that can be used to configure your switches with what appears to be enough permission for PRTG (or a similar SNMP monitoring system) to keep an eye on them. After entering configuration mode a readonly view with a… Read more
FreeIPA to Palo Alto Networks Next Generation Firewall User-ID
Logs from the FreeIPA server can be used with the Syslog receiver function of a PAN NGFW to send username to IP address mappings into User-ID and in turn be used to create policies based on the users identity. To extract the data from the logs you will need the parser shown below. View the code on Gist. I could… Read more
Palo Alto Networks Captive Portal, long delay in loading – Sophos agent
In recently deploying the Captive Portal feature of a Palo Alto Networks Next Generation Firewall (NGFW) in testing we were finding Apple Macs take 120+ seconds to load the sign-in page. First thoughts jumped to the Apple Captive Network Assistance (CNA) feature not functioning correctly however this appeared to be a dead end. Some time and a few packet captures… Read more
CITC 2023 All of this has happened before. All of this will happen again.
This presentation covers the MITRE ATT&CK matrix and it’s application in an Oxford or Cambridge College (or indeed any intuition) to gain increased awareness of exposure to cyber attacks and what can be done about them. Note, it looks like OBS captured the audio from the videos that wasn’t played back to the audience – sorry for talking over them!… Read more
FIDO2 Security Key Sign-In to Windows – Your credentials couldn’t be verified.
When setting up Passwordless security key sign-in Windows and attempting to sign-in to the first machine you have setup (although it could be any machine!) you may encounter the error: Your credentials couldn’t be verified. (code: 0x000006d, 0x0) This error message appears even though you can sign-in with the key to AzureAD and other web services. The cause is likely… Read more
Ruckus Cloudpath – setting an SMTP server does not allow disabling of CAPTCHA
A bit of an odd one here (and has been reported to Ruckus as something that either needs clarifying or fixing) in that if you want to remove the requirement for CAPTCHA when self registering in a ‘out of band’ workflow block you need to configure your own SMTP server. Now that’s all fair however even with the server configured… Read more
CITC 2022 Integrating systems through their APIs
After a few years on hold it’s great to be back at CITC this time in the British Motor Museum. The video presentation covers a short (if speedy) introduction to Node-RED and it’s ability to integrate systems through their APIs. Demo 2 is of note and shows how a user visiting a malicious website can have their internet access revoked… Read more