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polarssl -- Timing attack against protected RSA-CRT implementation

Affected packages
polarssl < 1.2.9


VuXML ID ccefac3e-2aed-11e3-af10-000c29789cb5
Discovery 2013-10-01
Entry 2013-10-02

PolarSSL Project reports:

The researchers Cyril Arnaud and Pierre-Alain Fouque investigated the PolarSSL RSA implementation and discovered a bias in the implementation of the Montgomery multiplication that we used. For which they then show that it can be used to mount an attack on the RSA key. Although their test attack is done on a local system, there seems to be enough indication that this can properly be performed from a remote system as well.

All versions prior to PolarSSL 1.2.9 and 1.3.0 are affected if a third party can send arbitrary handshake messages to your server.

If correctly executed, this attack reveals the entire private RSA key after a large number of attack messages (> 600.000 on a local machine) are sent to show the timing differences.


CVE Name CVE-2013-5915