What Are the Risks of eSIM? A Balanced Look at Real and Exaggerated Threats

eSIM technology is generally more secure than physical SIM cards, but it is not risk-free. The real risks include SIM swap fraud (which affects both SIM types equally), carrier system vulnerabilities, phishing attacks targeting eSIM credentials, complex device transfer procedures that can leave your number in limbo, and the inability to physically disconnect from a network. Most of the dangers people worry about are either shared with traditional SIM cards or significantly reduced by the embedded design of eSIM. However, new research in 2025 uncovered genuine hardware-level vulnerabilities in certain eSIM chipsets that deserve attention. This article separates the risks that are real and actionable from those that are exaggerated or misunderstood, and provides practical steps to protect yourself.

Risk 1: SIM Swap Fraud (Real, But Not Worse Than Physical SIM)

SIM swap fraud remains the most widely discussed security risk associated with mobile connectivity, and it applies equally to eSIM and physical SIM. In a SIM swap attack, a criminal contacts your carrier, impersonates you using stolen personal information (name, address, date of birth, last four digits of your Social Security number or equivalent), and convinces the carrier to transfer your phone number to a SIM they control. Once successful, the attacker receives all your incoming calls and SMS, including two-factor authentication codes from banks, email providers, and social media accounts.

The critical point is that SIM swap fraud is a social engineering attack against the carrier's customer verification process, not a technical attack against the SIM itself. Whether you use a physical SIM or an eSIM, the vulnerability is identical: it depends on how rigorously your carrier verifies identity before making changes to your account. A carrier with weak verification processes is equally vulnerable regardless of which SIM format their customers use.

Some carriers have actually implemented stronger verification for eSIM transfers than for physical SIM replacements, because eSIM changes happen digitally and can be gated behind multi-factor authentication in carrier apps. In contrast, a physical SIM replacement at a retail store may only require showing an ID, which can be forged. The perception that eSIM is more vulnerable to SIM swapping is not supported by the technical reality.

How to protect yourself: Enable a PIN or password on your carrier account that must be provided for any account changes. Use app-based two-factor authentication (Google Authenticator, Authy, or similar) instead of SMS-based 2FA wherever possible. Monitor your carrier account for unauthorized changes. If your phone suddenly loses service unexpectedly, contact your carrier immediately as this may indicate a SIM swap in progress.

Risk 2: Phishing and Social Engineering (Real, Growing Threat)

Phishing attacks specifically targeting eSIM users have increased as the technology has become more mainstream. These attacks take several forms.

Fake QR codes. Criminals distribute counterfeit QR codes through fraudulent websites, emails, or even physical posters placed in airports and hotels frequented by travellers. Scanning a malicious QR code could install a compromised eSIM profile or redirect you to a phishing site designed to steal your carrier login credentials. Always obtain eSIM QR codes directly from your carrier's official app, website, or a verified email from the provider.

Carrier impersonation. Attackers send emails or SMS messages that appear to come from your carrier, claiming there is an issue with your eSIM that requires immediate action. The message includes a link to a fake carrier website where you are asked to enter your account credentials. Once captured, these credentials can be used to initiate unauthorized eSIM transfers.

Fake eSIM provider scams. With hundreds of travel eSIM providers now operating globally, some fraudulent operators have appeared, offering extremely cheap plans that serve as a front for collecting payment information and personal data. Stick to established providers with verified reviews, and research any unfamiliar eSIM company before purchasing. Comparison sites like eSIM Card List can help you identify legitimate, well-reviewed providers.

How to protect yourself: Never scan QR codes from untrusted sources. Only download eSIM profiles through your carrier's official channels. Verify the sender of any email or SMS claiming to be from your carrier before clicking links. Use unique, strong passwords for carrier accounts and enable two-factor authentication.

Risk 3: Hardware-Level Vulnerabilities (Real, Addressed by Industry)

In mid-2025, security researcher Adam Gowdiak of Security Explorations demonstrated a genuine hardware-level vulnerability in eSIM chipsets manufactured by Kigen, one of the major eUICC (embedded Universal Integrated Circuit Card) suppliers. The vulnerability exploited long-standing flaws in the Java Card technology that runs on many eUICC chips, allowing an attacker with initial physical access to extract cryptographic keys and subsequently install malicious applets over-the-air without triggering security alerts.

In a proof-of-concept demonstration, a researcher was able to clone a commercial eSIM, causing calls, texts, and two-factor codes to route to a cloned device without alerting the original user. IBM's security analysis of this vulnerability noted that similar weaknesses might exist in eUICC implementations from other major suppliers including Thales and NXP, because many share similar Java Card virtual machine environments.

Kigen responded with a security bulletin and released an over-the-air patch for affected devices. The vulnerability received a medium severity rating (CVSS 6.7) because exploiting it requires initial physical access to the chip, which limits the practical attack surface significantly.

This discovery is important because it demonstrates that eSIM hardware is not immune to vulnerabilities, and that the security of the entire system depends on proper implementation by chipset manufacturers, not just the GSMA's provisioning protocol standards. However, it is equally important to note that physical SIM cards have their own well-documented history of hardware vulnerabilities, cloning techniques, and supply chain risks. The eSIM vulnerability was discovered, disclosed responsibly, and patched, which is the security process working as intended.

How to protect yourself: Keep your phone's operating system updated, as OS updates include security patches for the eUICC firmware. Purchase phones from reputable manufacturers who commit to long-term security updates. Monitor security advisories from your device manufacturer and carrier.

Risk 4: Carrier System Breaches (Real, But Applies to All SIM Types)

eSIM profiles are provisioned and managed through carrier server infrastructure, specifically the SM-DP+ (Subscription Manager Data Preparation) servers that store and deliver carrier profiles. If a carrier's provisioning infrastructure is compromised through a data breach, attackers could theoretically access eSIM profile data, subscriber credentials, and the provisioning keys used to activate eSIM profiles on devices.

This risk is real but not unique to eSIM. Carriers store subscriber data for physical SIM customers in the same types of databases (Home Location Register, Home Subscriber Server) that are equally valuable targets for attackers. A carrier breach affects all customers regardless of SIM format.

The eSIM provisioning process does introduce additional server infrastructure (SM-DP+ and SM-DS servers) that creates an expanded attack surface compared to the physical SIM distribution model. The GSMA's Remote SIM Provisioning specification includes mandatory security requirements for these servers, including end-to-end encryption, mutual TLS authentication, and certificate-based trust chains. Carriers that properly implement these standards maintain a robust security posture.

How to protect yourself: Choose carriers with strong security reputations and transparent data protection policies. Enable all available security features on your carrier account. Use unique passwords for your carrier account that are not reused elsewhere. Monitor your account for unauthorized activity.

Risk 5: Complex Device Transfers (Real Usability Risk)

One of the most practically impactful risks of eSIM is not a security threat but a usability challenge that can temporarily leave you without phone service. When transferring an eSIM from one device to another, the process involves deactivating the profile on the old device and provisioning it on the new one, coordinated through the carrier's systems.

When this process fails (due to server errors, connectivity issues, app glitches, or carrier policy complications), your phone number can end up in a state where it is not active on either device. Resolving this situation typically requires contacting your carrier's support team, which may authenticate your identity via SMS, creating a problematic catch-22 when you cannot receive SMS because your service is disrupted.

A widely reported case in late 2025 involved a technology journalist whose phone number became stuck during eSIM transfers on two separate occasions within three months after switching to Google's eSIM-only Pixel 10. The resolution required in-person visits to carrier retail stores, turning what should have been a seconds-long process into multi-hour ordeals.

This risk is particularly acute for users who switch devices frequently, travellers who may need to restore service on a backup phone in areas without reliable internet, and anyone experiencing a phone failure who needs immediate connectivity restoration.

How to protect yourself: Before transferring your eSIM, ensure you have a stable Wi-Fi connection. Do not delete your eSIM profile from the old device until the new device is fully activated and working. Keep your carrier's customer service number accessible from another device or written down. If your phone supports it, use your carrier's official eSIM Quick Transfer tool rather than manual QR code methods. Consider keeping a physical SIM as a backup if your phone has a SIM tray.

Risk 6: Inability to Physically Disconnect (Partially Valid Concern)

With a physical SIM, you can remove the card from your phone to guarantee that the device is completely disconnected from the cellular network. Some privacy-conscious individuals and people in sensitive professions value this ability to create an absolute air gap between their phone and the carrier's infrastructure.

With eSIM, you can disable the profile through software settings, but you cannot physically remove the chip. While disabling an eSIM line in settings effectively stops the device from communicating with the cellular network (just as turning off a physical SIM line does), some users do not fully trust that a software toggle provides the same absolute disconnection as physically removing hardware.

From a technical perspective, a disabled eSIM profile does not communicate with the network. The eUICC chip enters an idle state where it performs no authentication or registration activity. However, other components of the phone (Wi-Fi, Bluetooth, GPS) can still transmit data, and the phone's baseband processor could theoretically be targeted by sophisticated state-level attacks regardless of SIM type.

For the vast majority of users, the software toggle provides entirely adequate disconnection. For individuals facing genuine surveillance threats (journalists in authoritarian countries, activists, certain government employees), the inability to physically remove the SIM is a valid concern, though it should be weighed against the broader attack surface of the device itself.

How to protect yourself: Use Airplane Mode for a quick disconnect of all wireless communications. Disable individual eSIM lines in settings when not in use. For maximum privacy, power off the device entirely. Consider the overall threat model rather than focusing solely on the SIM as a privacy vector.

Risk 7: Data Routing and Privacy in Travel eSIMs (Often Overlooked)

A less discussed risk involves how travel eSIM providers route your data. When you use a travel eSIM, your data may be routed through the provider's home network infrastructure rather than staying local to the country you are visiting. This means your internet traffic could pass through servers in a third country before reaching its destination, potentially exposing it to different privacy regulations and surveillance frameworks.

Some travel eSIM providers use Local Breakout (LBO), which keeps your data within the visited country's network. Others use Home Routed Roaming (HRR), which routes data back through their home network. The routing method affects which jurisdictions your data passes through and which entities can potentially inspect it.

This is not a vulnerability in eSIM technology itself but rather a business practice consideration that users should be aware of when choosing a travel eSIM provider. Providers that use LBO generally offer better privacy for local data, while HRR providers may offer more consistent pricing but route data through additional network hops.

How to protect yourself: Research your travel eSIM provider's data routing practices before purchasing. Use a VPN to encrypt all internet traffic regardless of how the underlying data is routed. Choose providers that are transparent about their network partners and routing policies.

What eSIM Protects You From (Risks That Disappear)

While focusing on eSIM risks, it is important to acknowledge the risks that eSIM eliminates entirely, risks that physical SIM users face daily.

Physical theft of the SIM card. A stolen physical SIM gives an attacker your phone number. A stolen phone with eSIM gives them nothing useful because the profile requires carrier authorization to transfer.

SIM cloning through physical access. Physical SIM cards can be cloned by reading data from the card with specialized equipment. eSIM profiles are stored in a secure element that is extremely difficult to extract data from without the kind of advanced attack described in Risk 3.

Loss of the SIM card. Physical SIMs are tiny and easily lost when removed from a phone. eSIM cannot be lost because it is part of the device.

Supply chain interception. Physical SIMs can theoretically be intercepted during manufacturing or postal delivery and tampered with before reaching the customer. eSIM profiles are delivered through encrypted digital channels, eliminating the physical supply chain risk.

Conclusion

The risks of eSIM are real but manageable, and in most categories, eSIM is equal to or more secure than physical SIM. The primary risks that apply specifically to eSIM are complex device transfers that can temporarily disrupt service, the inability to physically remove the SIM for absolute disconnection, and hardware vulnerabilities in eUICC chipsets that are actively being patched by manufacturers. SIM swap fraud, phishing, carrier breaches, and data privacy concerns affect both SIM types equally and depend more on carrier practices and user behaviour than on the SIM format. For the overwhelming majority of users, eSIM reduces overall risk compared to physical SIM while introducing a small number of new considerations that can be addressed through awareness and basic security hygiene.