Other nomination

HostSplit: Exploitable Antipatterns in Unicode Normalization

Jonathan Birch

Some Unicode characters normalise under NFKC to ASCII with URL syntax meaning, so a hostname validated as a subdomain of a trusted site resolves as a different host plus a path, bypassing allow-lists and stealing OAuth tokens. HostBond is the reverse: punycode decoded for display lets an attacker domain render as a trusted host or email sender.

Record

Researcher

Jonathan Birch

Format

Whitepaper

In the archive

• Nominated for the 2019 Top 10 Web Hacking Techniques

Related sources

• Talk recording

Tags

• unicode
• url-parsing
• parser-differential
• open-redirect
• oauth
• filter-bypass
• email
• encoding
• cve
• owasp-a04-2021
• owasp-a05-2021
• owasp-a07-2021

This page is the archive's own catalogue record. The research is the work of Jonathan Birch, first published at the original source. Preserved copies are kept so the citation survives its host.