Introducing HAR Sanitizer: secure HAR sharing

On Wednesday, October 18th, 2023, Cloudflare’s Security Incident Response Team (SIRT) discovered an attack on our systems that originated from an authentication token stolen from one of Okta’s support systems. No Cloudflare customer information or systems were impacted by the incident, thanks to the real-time detection and rapid action of our Security Incident Response Team (SIRT) in tandem with our Zero Trust security posture and use of hardware keys. With that said, we’d rather not repeat the experience — and so we have built a new security tool that can help organizations render this type of attack obsolete for good.
The bad actor in the Okta breach compromised user sessions by capturing session tokens from administrators at Cloudflare and other impacted organizations. They did this by infiltrating Okta’s customer support system and stealing one of the most common mechanisms for troubleshooting — an HTTP Response Archive (HAR) file.
HAR files contain a record of a user’s browser session, a kind of step-by-step audit, that a user can share with someone like a help desk agent to diagnose an issue. However, the file can also contain sensitive information that can be used to launch an attack.
As a follow-up to the Continue reading



