Top 10 winner

Lucky 13 Attack

Lucky Thirteen: Breaking the TLS and DTLS Record Protocols

Nadhem AlFardan and Kenny Paterson · isg.rhul.ac.uk

TLS and DTLS CBC decryption runs measurably faster when a record carries at least two bytes of valid padding, because the 13-byte MAC header aligns hash compression blocks differently. Timing TLS error messages on a LAN and averaging out jitter recovers a plaintext block in about 2^23 sessions, fewer with base64 or BEAST-style tricks; DTLS falls in a single session.

Record

Document

Lucky Thirteen: Breaking the TLS and DTLS Record Protocols

Researcher

Nadhem AlFardan and Kenny Paterson

Published by

isg.rhul.ac.uk

Topic

Other

In the archive

• Ranked #4 in the 2013 Top 10 Web Hacking Techniques

Related sources

• Lucky Thirteen Whitepaper
• DTLS timing amplification Whitepaper

Tags

• tls
• timing-attack
• side-channel
• https
• mitigation
• owasp-a02-2021

This page is the archive's own catalogue record. The research is the work of Nadhem AlFardan and Kenny Paterson, 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.