Cybersecurity researchers have found a contemporary set of safety points within the Terrestrial Trunked Radio (TETRA) communications protocol, together with in its proprietary end-to-end encryption (E2EE) mechanism that exposes the system to replay and brute-force assaults, and even decrypt encrypted visitors.
Particulars of the vulnerabilities – dubbed 2TETRA:2BURST – have been introduced on the Black Hat USA safety convention final week by Midnight Blue researchers Carlo Meijer, Wouter Bokslag, and Jos Wetzels.
TETRA is a European cell radio customary that is broadly utilized by regulation enforcement, army, transportation, utilities, and significant infrastructure operators. It was developed by the European Telecommunications Requirements Institute (ETSI). It encompasses 4 encryption algorithms: TEA1, TEA2, TEA3, and TEA4.
The disclosure comes a bit of over two years after the Netherlands-based cybersecurity firm found a set of safety vulnerabilities in TETRA customary known as TETRA:BURST, counting what was described as an “intentional backdoor” that might be exploited to leak delicate info.
The newly found points relate to a case of packet injection in TETRA, in addition to an inadequate repair for CVE-2022-24401, one of many 5 TETRA:BURST points, to stop keystream restoration assaults. The recognized points are listed beneath –
- CVE-2025-52940 – TETRA end-to-end encrypted voice streams are weak to replay assault. Moreover, an attacker with no data of the important thing might inject arbitrary voice streams, which might be performed again indistinguishably from genuine visitors by respectable name recipients.
- CVE-2025-52941 – TETRA end-to-end encryption algorithm ID 135 refers to an deliberately weakened AES-128 implementation which has its efficient visitors key entropy lowered from 128 to 56 bits, rendering it weak to brute-force assaults.
- CVE-2025-52942 – Finish-to-end encrypted TETRA SDS messages characteristic no replay safety, permitting for arbitrary replay of messages in the direction of both people or machines.
- CVE-2025-52943 – TETRA networks that help a number of Air Interface Encryption algorithms are weak to key restoration assaults because the SCK/CCK community key’s similar for all supported algorithms. When TEA1 is supported, an simply recovered TEA1 key (CVE-2022-24402) can be utilized to decrypt or inject TEA2 or TEA3 visitors on the community.
- CVE-2025-52944 – The TETRA protocol lacks message authentication and due to this fact permits for the injection of arbitrary messages corresponding to voice and information.
- ETSI’s repair for CVE-2022-24401 is ineffective within the prevention of keystream restoration assaults (No CVE, assigned a placeholder identifier MBPH-2025-001)
Midnight Blue stated the influence of the 2TETRA:2BURST rely on the use-cases and configuration points of every specific TETRA community, and that networks that use TETRA in a data-carrying capability are significantly vulnerable to packet injection assaults, doubtlessly permitting attackers to intercept radio communications and inject malicious information visitors.
“Voice replay or injection situations (CVE-2025-52940) could cause confusion amongst respectable customers, which can be utilized as an amplifying consider a larger-scale assault,” the corporate stated. “TETRA E2EE customers (additionally these not utilizing Sepura Embedded E2EE) ought to in any case validate whether or not they could be utilizing the weakened 56-bit variant (CVE-2025-52941).”
“Downlink visitors injection is usually possible utilizing plaintext visitors, as we discovered radios will settle for and course of unencrypted downlink visitors even on encrypted networks. For uplink visitors injection, the keystream must be recovered.”
There is no such thing as a proof of those vulnerabilities being exploited within the wild. That stated, there are not any patches that deal with the shortcomings, apart from MBPH-2025-001, for which a repair is predicted to be launched.
Mitigations for different flaws are listed beneath –
- CVE-2025-52940, CVE-2025-52942 – Migrate to scrutinized, safe E2EE resolution
- CVE-2025-52941 – Migrate to non-weakened E2EE variant
- CVE-2025-52943 – Disable TEA1 help and rotate all AIE keys
- CVE-2025-52944 – When utilizing TETRA in a knowledge carrying capability: add TLS/VPN layer on high of TETRA
“For those who function or use a TETRA community, you might be definitely affected by CVE-2025-52944, by which we display it is attainable to inject malicious visitors right into a TETRA community, even with authentication and/or encryption enabled,” Midnight Blue stated.
“Additionally, CVE-2022-24401 seemingly impacts you, because it permits adversaries to gather keystream for both breach of confidentiality or integrity. For those who function a multi-cipher community, CVE-2025-52943 poses a essential safety threat.”
In an announcement shared with WIRED, ETSI stated the E2EE mechanism utilized in TETRA-based radios isn’t a part of the ETSI customary, including it was produced by The Important Communications Affiliation’s (TCCA) safety and fraud prevention group (SFPG). ETSI additionally famous that purchasers of TETRA-based radios are free to deploy different options for E2EE on their radios.
The findings additionally coincide with the invention of three flaws within the Sepura SC20 sequence of cell TETRA radios that enable attackers with bodily entry to the system to attain unauthorized code execution –
- CVE-2025-52945 – Faulty file administration restrictions
- CVE-2025-8458 – Inadequate key entropy for SD card encryption
- Exfiltration of all TETRA and TETRA E2EE key supplies apart from the device-specific key Okay (no CVE, assigned a placeholder identifier MBPH-2025-003)
Patches for CVE-2025-52945 and CVE-2025-8458 are anticipated to be made out there within the third quarter of 2025, necessitating that customers are suggested to implement enhanced TETRA key administration insurance policies. MBPH-2025-003, then again, can’t be remediated resulting from architectural limitations.
“The vulnerabilities allow an attacker to achieve code execution on a Sepura Gen 3 system,” the corporate stated. “Assault situations that includes CVE-2025-8458 contain persistent code execution by way of entry to a tool’s SD card. Abuse of CVE-2025-52945 is much more simple because it requires solely transient entry to the system’s PEI connector.”
“From the premise of code execution, a number of assault situations are viable, corresponding to exfiltration of TETRA key supplies (MBPH-2025-003) or the implantation of a persistent backdoor into the radio firmware. This results in the lack of confidentiality and integrity of TETRA communications.”
