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Flaw Crippling Millions of Crypto Keys Is Worse Than First Disclosed (arstechnica.com)

An anonymous reader quotes a report from Ars Technica: A crippling flaw affecting millions -- and possibly hundreds of millions -- of encryption keys used in some of the highest-stakes security settings is considerably easier to exploit than originally reported, cryptographers declared over the weekend. The assessment came as Estonia abruptly suspended 760,000 national ID cards used for voting, filing taxes, and encrypting sensitive documents. The critical weakness allows attackers to calculate the private portion of any vulnerable key using nothing more than the corresponding public portion. Hackers can then use the private key to impersonate key owners, decrypt sensitive data, sneak malicious code into digitally signed software, and bypass protections that prevent accessing or tampering with stolen PCs. When researchers first disclosed the flaw three weeks ago, they estimated it would cost an attacker renting time on a commercial cloud service an average of $38 and 25 minutes to break a vulnerable 1024-bit key and $20,000 and nine days for a 2048-bit key. Organizations known to use keys vulnerable to ROCA—named for the Return of the Coppersmith Attack the factorization method is based on—have largely downplayed the severity of the weakness.

On Sunday, researchers Daniel J. Bernstein and Tanja Lange reported they developed an attack that was 25 percent more efficient than the one created by original ROCA researchers. The new attack was solely the result of Bernstein and Lange based only on the public disclosure information from October 16, which at the time omitted specifics of the factorization attack in an attempt to increase the time hackers would need to carry out real-world attacks. After creating their more efficient attack, they submitted it to the original researchers. The release last week of the original attack may help to improve attacks further and to stoke additional improvements from other researchers as well.

4 of 76 comments (clear)

  1. Re:Organizations known to use keys vulnerable to R by Anonymous Coward · · Score: 0, Insightful

    That's not what I'm asking. I want a list of vendors to see who I might be using, but we always get the runaround on this.

  2. Re:Online voting in Estonia by Anonymous Coward · · Score: 0, Insightful

    All NSA cyber attacks are now routinely pushed through Russian servers in an effort to "implicate" Russia in ALL cyber attacks that they carry out.
    But it wasn't RUSSIA that created Stuxnet, nor the base code for a STRING of recent hacking tools.

  3. Re:National ID cards used for voting? by Anonymous Coward · · Score: 2, Insightful

    4M+ illegal voters on 11/8/16.

    (In a very tired voice)

    Evidence, please?

  4. Re:Online voting in Estonia by Anonymous Coward · · Score: 2, Insightful

    Count yourself lucky. The Chinese would have eaten it!