When the exploit crashes SMS messaging on a phone, the phone remains otherwise completely functional. The only effect is that it cannot receive any new SMS/MMS messages.
Exploit:SymbOS/SMSCurse.A affects Series 60 (S60) phones running:
- S60 2nd Edition, Feature Pack 2
- S60 2nd Edition, Feature Pack 3
- S60 3rd Edition (initial release)
- S60 3rd Edition, Feature Pack 1
These versions of Series 60 contain an SMS vulnerability that can be exploited. SMSCurse.A is a specifically formatted SMS message that will crash the SMS messaging service of vulnerable phones.
Only one exploit message will crash the messaging service of S60 2nd Edition, Feature Pack 2 and S60 3rd Edition (initial release) phones.
Several messages are required to crash the messaging service of S60 2nd Edition, Feature Pack 3 and S60 3rd Edition, Feature Pack1 phones.
Phones that can be DoS with only one exploit message present no evidence of attack.
Phones that require several messages produce the following error once the service is jammed:
- Not enough memory to receive message(s). Delete some data first.
The main display phone will repeatedly flash a message icon. The user will not receive any new messages. Restarting these phones will restore limited, but fragile functionality. One new SMS message may be received before the service crashes again. A multi-part SMS message may crash the service to the point that a restart of the phone fails to restore any functionality.
Backing up the phone will also back up the exploit messages and will not repair the exploit.
Devices that use Symbian OS 9.3 are not affected. S60 3rd Edition, Feature Pack 2 and S60 5th Edition phones are not vulnerable.