Forging 1024-bit RSA signatures in nearly SNFS time [pdf](eprint.iacr.org) |
Forging 1024-bit RSA signatures in nearly SNFS time [pdf](eprint.iacr.org) |
So it's not a straightforward general-purpose RSA-1024 signature break; it's pretty situational. The paper goes into detail (in section 5) about how those situations can emerge in practical scenarios.