Revision a281464e
Added by osmith about 4 years ago
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A long-standing issue in the 3GPP specifications is, that mobile phones and |
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other mobile equipment (ME) have to send the International Mobile Subscriber |
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Identity (IMSI) unencrypted over the air. Each IMSI is a unique identifier for |
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the subscriber Therefore most people can be uniquely identified by recording the
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IMSI that their ME is sending. The 3GPP specifications provide means for |
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the subscriber. Therefore most people can be uniquely identified by recording
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the IMSI that their ME is sending. The 3GPP specifications provide means for
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implementations to send the IMSI less often by using the Temporary Mobile |
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Subscriber Identity (TMSI) where possible. |
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the HLR has both the old and the new pseudonymous IMSI allocated at this point, |
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the subscriber is not locked out of the network. |
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=== Next Pseudonymous IMSI SMS arrives out of order
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=== Next Pseudonymous IMSI SMS Arrives Out of Order
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The next pseudonymous IMSI SMS may arrive out of order. Either, because the |
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network is not able to deliver them in order, or even because an attacker would |
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network. |
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The safest way to protect the next pseudonymous IMSI SMS is a layer of end to |
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end encryption from the HLR to the SIM. The existing means for OTA SMS security
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(3GPP TS 23.048) provide mechanisms for integrity protection, confidentiality
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as well as replay protection and must be implemented when using IMSI
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pseudonymization. |
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end encryption from the HLR to the SIM. The existing means for OTA SMS |
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security (3GPP TS 23.048) provide mechanisms for integrity protection,
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confidentiality as well as replay protection and must be implemented when using
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IMSI pseudonymization.
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=== User-configurable Minimum Duration Between IMSI Changes |
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Also available in: Unified diff
spec: minor fixes, wrap text