Dear all,
Bleichenbacher's attack shows that it was possible to forge a PKCS #1
v1.5 signature signed by a key using exponent 3.

Unfortunately the implementation of the OpenSSL command
        openssl genrsa ...
allows only to create keys with exponent 3 or F4. Nevertheless the new
RSA key generation routine RSA_generate_key_ex available in 0.9.8 works
already with arbitrary exponents.

The included minor patch of apps/genrsa.c adds a new option for exponent
selection to the genrsa command.

Because OpenSSL version 0.9.7 doesn't use RSA_generate_key_ex with
exponents BIGNUM but unsigned long, this patch is applicable to version
0.9.8++ only.

Regards,
Ann

--
    Annie Yousar at egbg dot de

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