Deutsche Telekom has introduced a so-called “SMS-Firewall” as of April 1, 2025, to ward off misuse and warn of dangerous short messages. This new system is designed to analyze all incoming messages for known dangers, such as links to fraudulent content or malware, and stop them from reaching customers.
The company explains that this analysis is based on the numerical value of the message, which is compared to a database of known threats. It’s essential to note that this process doesn’t involve evaluating the meaning of the words in the message. Instead, it’s a purely numerical comparison to identify potential risks.
According to Telekom’s data protection instructions, if there’s a reasonable suspicion that an SMS contains abusive content, such as spam, scam, or malware, the company can block these messages to protect the integrity of its networks and the legal goods of its customers. This measure is aimed at preventing harm to both Telekom and its users.
Specifically, the SMS-Firewall checks this information:
* Technical data, including sending and receiving information, date, and time
* Contained links to malignant content, such as malware
Depending on the assessment, Telekom can either block the SMS or allow it to reach the recipient. However, there are cases where an SMS might not contain a link but still be an attempted fraud. In such instances, Telekom may still block the message, as it cannot definitively determine whether the content is fraudulent.
Telekom’s mobile customers don’t need to take any action to benefit from the new SMS firewall, as it is automatically active for all customers starting from April 1, 2025.
According to Telekom, law prevents further protection
While the SMS-Firewall provides a significant level of protection, Telekom believes that the current legal situation prevents it from offering even more extensive protection. The company explains that, from a technical standpoint, it could protect its customers further, but the law does not allow it to evaluate the content of SMS messages. This limitation means that Telekom cannot stop fraud attempts based solely on the text in the SMS, as it is not permitted to read and assess the content of short messages.
As a result, the new SMS firewall may not be able to stop certain types of scams, such as those using the “grandchildren trick,” where the scammer sends a message pretending to be a grandchild in need of help.
Vodafone and 1 & 1
Deutsche Telekom is not the first company to introduce such protection against fraudulent SMS. Vodafone and 1 & 1 have already implemented similar protective measures, as reported by Deutschlandfunk. This move by Telekom is part of a broader effort by telecommunications companies to combat the growing threat of SMS-based scams and protect their customers from potential harm.
