TETRA Standard: Authorization Bypass Through User-Controlled Key
CVE-2022-24401 is a high-severity authorization bypass through user-controlled key vulnerability in TETRA Standard from ETSI, with a CVSS 3.1 base score of 8.1 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. Affected TETRA Standard versions: all. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.34% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of TETRA Standard you run against the affected versions below, and install the vendor's latest release.
- Read the advisory on tetraburst.com for workarounds and exact fixed builds.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| ETSI | TETRA Standard | all | Not stated |
| Midnightblue | Tetra | burst | Not stated |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- AdjacentThe attacker must be on the same local network segment.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N. Scored by NVD.
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 3.1 | 8.8 | High | CNA (ncsc.nl) |
| CVSS 3.1 | 8.1 | High | NVD |
Official description
Adversary-induced keystream re-use on TETRA air-interface encrypted traffic using any TEA keystream generator. IV generation is based upon several TDMA frame counters, which are frequently broadcast by the infrastructure in an unauthenticated manner. An active adversary can manipulate the view of these counters in a mobile station, provoking keystream re-use. By sending crafted messages to the MS and analyzing MS responses, keystream for arbitrary frames can be recovered.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Authorization Bypass Through User-Controlled Key
The system's authorization functionality does not prevent one user from gaining access to another user's data or record by modifying the key value identifying the data.
How developers prevent this class of flaw
- For each and every data access, ensure that the user has sufficient privilege to access the record that is being requested.
- Make sure that the key that is used in the lookup of a specific user's record is not controllable externally by the user or that any tampering can be detected.
- Use encryption in order to make it more difficult to guess other legitimate values of the key or associate a digital signature with the key so that the server can verify that there has been no tampering.
More Authorization Bypass Through User-Controlled Key vulnerabilities (CWE-639)
Timeline
- CVE record published.
- Record last changed materially (score, affected products, status or references).
References
Advisories
Other vulnerabilities in TETRA Standard
- 7.5 High severity
- 7.5 High severity
Recent Authorization Bypass Through User-Controlled Key vulnerabilities
- 9.8 Critical severity
- 9.1 Critical severity
- 8.8 High severity
- 8.8 High severity
- 9.1 Critical severity
- 8.1 High severity
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