Daniel Bleichenbacher

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Daniel Bleichenbacher (born 1964) is a Swiss cryptographer, previously a researcher at Bell Labs and Google, and currently employed at Cure53. He received his Ph.D. from ETH Zurich in 1996 for contributions to computational number theory, particularly concerning message verification in the ElGamal and RSA public-key cryptosystems. [1] His doctoral advisor was Ueli Maurer.

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RSA Attacks

Bleichenbacher is particularly notable for devising attacks against the RSA public-key cryptosystem, namely when used with the PKCS#1 v1 standard published by RSA Laboratories. These attacks were able to break both RSA encryption and signatures produced using the PKCS #1 standard.

BB'98 attack: chosen ciphertext attack against the RSA PKCS#1 encryption standard

In 1998, Daniel Bleichenbacher demonstrated a practical attack against systems using RSA encryption in concert with the PKCS #1 encoding function, including a version of the Secure Sockets Layer (SSL) protocol used by thousands of web servers at the time. [2] This attack was the first practical reason to consider adaptive chosen-ciphertext attacks.

BB'06 attack: signature forgery attack against the RSA PKCS#1 signature standard

In 2006 at a rump session at CRYPTO, Bleichenbacher described a "pencil and paper"-simple attack against RSA signature validation as implemented in common cryptographic toolkits. Both OpenSSL and the NSS security engine in Firefox were later found to be vulnerable to the attack, which would allow an attacker to forge the SSL certificates that protect sensitive websites. [3] [4]

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RSA (Rivest–Shamir–Adleman) is a public-key cryptosystem, one of the oldest widely used for secure data transmission. The initialism "RSA" comes from the surnames of Ron Rivest, Adi Shamir and Leonard Adleman, who publicly described the algorithm in 1977. An equivalent system was developed secretly in 1973 at Government Communications Headquarters (GCHQ), the British signals intelligence agency, by the English mathematician Clifford Cocks. That system was declassified in 1997.

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<span class="mw-page-title-main">DROWN attack</span> Security bug

The DROWN attack is a cross-protocol security bug that attacks servers supporting modern SSLv3/TLS protocol suites by using their support for the obsolete, insecure, SSL v2 protocol to leverage an attack on connections using up-to-date protocols that would otherwise be secure. DROWN can affect all types of servers that offer services encrypted with SSLv3/TLS yet still support SSLv2, provided they share the same public key credentials between the two protocols. Additionally, if the same public key certificate is used on a different server that supports SSLv2, the TLS server is also vulnerable due to the SSLv2 server leaking key information that can be used against the TLS server.

References

  1. ↑ "Bleichenbacher Thesis" (PS). cr.yp.to. Archived from the original on 2022-07-12.
  2. ↑ Bleichenbacher, Daniel (1998). "Chosen Ciphertext Attacks Against Protocols Based on the RSA Encryption Standard PKCS #1". Crypto '98: 1–12. Archived from the original (PS) on 2012-02-04. Retrieved 2011-12-07.
  3. ↑ Bleichenbacher's RSA signature forgery based on implementation error
  4. ↑ Analysis on Bleichenbacher's Forgery Attack. IEEE. 2007.
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