title: De-anonymization attack in TETRA
description: The TETRA TA61 identity encryption function internally uses a 64-bit value derived exclusively from the SCK (Class 2 networks) or CCK (Class 3 networks). The structure of TA61 allows for efficient recovery of this 64-bit value, allowing an adversary to encrypt or decrypt arbitrary identities given only three known encrypted/unencrypted identity pairs.
problem types: Use of a Broken or Risky Cryptographic Algorithm
affected:
{
vendor: ETSI
product: TETRA Standard
versions:
version: TA61, status: affected
}
metrics:
format: CVSS
scenarios: GENERAL
cvssV3_1: [
version: 3.1
attackVector: ADJACENT_NETWORK
attackComplexity: LOW
privilegesRequired: NONE
userInteraction: NONE
scope: UNCHANGED
confidentialityImpact: LOW
integrityImpact: NONE
availabilityImpact: NONE
baseScore: 4.3
baseSeverity: HIGH
vectorString: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N/E:F/RL:U/RC:C/CR:H/IR:H/AR:H/MAV:A/MAC:L/MPR:N/MUI:N/MS:U/MC:L/MI:N/MA:N
]