Digital Event Horizon
A critical encryption scheme used by law enforcement, military, and intelligence agencies worldwide has been found to have a reduced-key vulnerability that could compromise its security. This discovery raises serious concerns about the security of sensitive information shared over these systems and highlights the need for increased scrutiny and attention to the implementation of encryption standards.
The TCCA end-to-end encryption (E2EE) scheme has been found to have a reduced-key vulnerability that could compromise its security. The flaw in the protocol design affects all users of the scheme, regardless of implementation by different vendors. The vulnerability is attributed to flaws in the protocol's design rather than any specific implementation. The encryption algorithm used for this implementation starts with a 128-bit key but gets compressed to 56 bits before encrypting traffic, making it easier to crack. The TCCA E2EE solution is most commonly used in radios for law enforcement agencies, special forces, and covert military and intelligence teams that require an extra layer of security. The discovery raises serious concerns about the security of sensitive information shared over these systems.
The revelation that a critical encryption scheme used by law enforcement, military, and intelligence agencies around the world is vulnerable to eavesdropping has sent shockwaves throughout the security community. The TCCA end-to-end encryption (E2EE) scheme, designed to provide secure communication for sensitive information, has been found to have a reduced-key vulnerability that could compromise its security.
According to researchers, this flaw in the TCCA E2EE protocol design affects all users of the scheme, regardless of implementation by different vendors. The researchers attribute this issue to flaws in the protocol's design rather than any specific implementation. Furthermore, law enforcement end-users have confirmed to them that this vulnerability is present in radios produced by vendors other than Sepura.
The TCCA E2EE scheme was originally designed as a solution to meet export controls for encryption sold to customers outside of Europe. The TEA1 key, which was initially considered secure for most uses, has been reduced to 32 bits due to advances in computing power. This reduction makes it easier to crack the encryption, rendering it less secure.
The European Telecommunications Standards Institute (ETSI) developed the TETRA standard, which includes four encryption algorithms: TEA1, TEA2, TEA3, and TEA4. The algorithms have different levels of security based on whether the radios will be sold in or outside Europe. TEA2 is restricted for use in radios used by police, emergency services, military, and intelligence agencies in Europe, while TEA3 is available for police and emergency services radios used outside Europe but only in countries deemed "friendly" to the EU.
However, a recent discovery has revealed that at least one implementation of the TCCA E2EE solution endorsed by ETSI has a similar issue. The encryption algorithm used for this implementation starts with a 128-bit key but gets compressed to 56 bits before encrypting traffic, making it easier to crack. It is unclear who is using this implementation or if anyone aware of the security vulnerability in their devices.
The TCCA E2EE solution is most commonly used in radios for law enforcement agencies, special forces, and covert military and intelligence teams that require an extra layer of security. The fact that ETSI's endorsement of the algorithm two years ago suggests it may be used more widely now than at the time.
In 2023, researchers discovered vulnerabilities in encryption algorithms that are part of a European radio standard created by ETSI called TETRA. These flaws remained unknown publicly until their disclosure, as ETSI refused to let anyone examine the proprietary algorithms for decades. The end-to-end encryption solution used with TETRA-based radios is not part of the ETSI standard nor was it created by the organization. Instead, it was produced by The Critical Communications Association's (TCCA) security and fraud prevention group (SFPG).
The TCCA group that developed the E2EE solution worked closely with ETSI, but their collaboration does not necessarily mean that ETSI is aware of the specific implementation used by different vendors. Brian Murgatroyd, former chair of the technical body at ETSI responsible for the TETRA standard as well as the TCCA group that developed the E2EE solution, wrote in an email on behalf of ETSI and the TCCA that end-to-end encryption was not included in the ETSI standard "because at the time it was considered that E2EE would only be used by government groups where national security concerns were involved."
The vast majority of police forces around the world use radios based on the TETRA standard, including those in Belgium and Scandinavian countries, as well as Eastern European countries like Serbia, Moldova, Bulgaria, and Macedonia. The Ministries of Defense in Bulgaria, Kazakhstan, and Syria also use them, as do the Polish military counterintelligence agency, the Finnish defense forces, and Lebanon and Saudi Arabia's intelligence services.
While it is unclear how many of these organizations deploy end-to-end encryption with their radios, the fact that this vulnerability exists raises serious concerns about the security of sensitive information shared over these systems. The researchers plan to present their findings today at the BlackHat security conference in Las Vegas.
In conclusion, the discovery of a reduced-key vulnerability in the TCCA E2EE scheme highlights the need for increased scrutiny and attention to the implementation of encryption standards used by critical infrastructure, law enforcement agencies, military forces, and intelligence agencies around the world. The impact of this flaw could be far-reaching, compromising the security of sensitive information shared over these systems.
Related Information:
https://www.digitaleventhorizon.com/articles/The-TCCA-E2EE-Encryption-Scheme-A-Flawed-Implementation-with-Far-Reaching-Consequences-deh.shtml
https://arstechnica.com/security/2025/08/encryption-made-for-police-and-military-radios-may-be-easily-cracked/
Published: Sat Aug 9 07:28:33 2025 by llama3.2 3B Q4_K_M
