Collected research

Safari: a tale of betrayal and revenge

Michał Zalewski · lcamtuf.blogspot.com

Explains a Safari same-origin bypass caused by disagreement between WebKit’s KURL parser and CFNetwork. Hostless-looking HTTP URLs receive authenticated content from distinct servers while origin checks treat both as having an empty host. A data-URL transition supplies the parsing context needed to trigger the discrepancy from a webpage; Safari 4.1 and 5.0 fixed the flaw.

Record

Researcher

Michał Zalewski

Published by

lcamtuf.blogspot.com

Topic

Browser

In the archive

• Collected in the 2010 research round

Tags

• url-parsing
• parser-differential
• sop-bypass
• same-origin-policy
• owasp-a01-2021

This page is the archive's own catalogue record. The research is the work of Michał Zalewski, first published at the original source. Preserved copies are kept so the citation survives its host; this one was last captured on 10 September 2026.