Smart locks face physical and new digital attack risks
Lena Hartmann, Home security editor (AI-assisted) ยท
The main difference between smart locks and traditional deadbolts is not the number of ways they are attacked, but the new kinds of vulnerabilities introduced by smart features. Real-world tests of five smart lock models found the same categories of physical attack as on deadbolts, but also exposed new risks unique to digital controls and wireless connections[3]. This article breaks down the attack methods, what testing found, and what this means for choosing and installing locks.
Attack methods: what does an intruder actually try?
Deadbolts and smart locks both face two main kinds of attack. For traditional deadbolts, these are:
- Physical force: Forcing or prying the bolt or door frame with tools (like crowbars or brute strength)[2].
- Bypassing the key mechanism: Picking, bumping, or otherwise manipulating the lock cylinder to turn the bolt without the key[2].
Smart locks, which are most often installed as upgrades to existing deadbolts, inherit these same two physical attack methods[1]. However, smart locks add electronic controls—and with those, new avenues for attack:
- Remote or digital compromise: Attacks on wireless connections, app vulnerabilities, or remote command channels[3].
- Credential abuse: Exploiting weak virtual keys, intercepted codes, or mismanaged access permissions[1].
Testing shows that, on the physical side, smart locks are only as strong as the deadbolt hardware they upgrade[3]. But attackers may not need to pick or force the lock at all if they can exploit the digital layer.
What security testing found in smart locks
A 2016 published study analyzed five commercially available smart lock models and found that design and implementation flaws could let attackers bypass authentication or learn private information, sometimes without physical access to the lock itself[3]. The tested devices were on the market at that time, but the study did not specify brands or firmware versions, and the findings may not reflect newer models or firmware updates since 2016.
The study identified two broad categories of weaknesses: physical, which are similar to attacks on traditional deadbolts, and digital, which are unique to smart locks. Examples from the digital category included:
- Poorly protected communications, where attackers could intercept or replay unlock commands[3].
- App or server design flaws, enabling remote attackers to gain unauthorized access or collect user data[3].
No source gives a precise count of how many smart locks currently on the market have these flaws; what the sources do show is that, in a limited 2016 sample of five models, vulnerabilities depended on both the specific device design and its smart feature setup[3]. If you are considering models released after 2016, check their published security advisories and firmware update policies for more current information.
Comparing attack methods: the numbers and what they mean
The attack surface for both deadbolts and smart locks starts the same: two main physical methods[2]. With smart locks, the number of distinct attack categories does not increase—there are still two main ways in—but the nature of those attacks changes:
- For deadbolts: all attacks are physical, with direct access to the door required[2].
- For smart locks: physical attacks remain, but attackers can also target digital weaknesses, sometimes from outside the home or even remotely[3].
The key difference is not in quantity, but in scope. While a deadbolt can only be bypassed on-site, a smart lock's vulnerabilities may be exploited from anywhere with internet access, depending on how its digital features are implemented[3]. This means that installing a smart lock on a strong deadbolt does not remove the risk of digital attack—it simply adds new things to secure.
A worked example: What happens if a smart lock’s app is compromised?
Suppose—as a hypothetical—someone installs a smart lock with Wi-Fi connectivity, managed through a mobile app, on a door secured by a standard single-cylinder deadbolt[2]. If an attacker is able to compromise the smart lock’s app, for example by capturing the virtual key through a network flaw, they could use the app’s own functions to disengage the deadbolt remotely, without needing to be at the door. In this scenario, the usual physical resistance of the deadbolt—against prying or picking—offers no barrier, since the lock’s electronics perform the action as if a trusted user requested it[3].
By contrast, if an intruder resorts to physical attacks like forcing the door or picking the lock, they encounter the same mechanical obstacles as they would with a traditional single-cylinder deadbolt. Adding smart features does not make the bolt itself easier to manipulate or less robust to force[2][3].
This constructed scenario illustrates that the meaningful risk introduced by smart functionality is the potential for remote, unauthorized operation if app controls are compromised; the underlying physical security remains unchanged.
Installation, configuration, and where mistakes undo the protection
The evidence shows that, for both deadbolts and smart locks, installation quality matters. A deadbolt that is not anchored into the frame, or a smart lock installed on a weak door, is vulnerable to the same forced entry methods[2]. But with smart locks, configuration errors add new risks:
- Weak or default app passwords can let attackers gain control remotely[3].
- Poor management of virtual keys or access logs can expose who enters and when[1].
- Failing to update firmware leaves known vulnerabilities unpatched[3].
None of these digital risks apply to a purely mechanical deadbolt. Owners who choose smart locks need to pay close attention to setup instructions, password hygiene, and software updates[1,3].
Questions readers ask
What’s the main reason to pick a smart lock over a deadbolt?
Smart locks offer keyless entry, remote access, and flexible sharing of virtual keys, which many users value for convenience and monitoring[1]. The tradeoff is the need to secure not just the hardware, but also the digital systems and user accounts that control access[1,3].
Does a smart lock make my door stronger against break-ins?
No. A smart lock installed on a standard deadbolt does not make the door more resistant to physical entry than the deadbolt alone[2,3]. The primary benefit is in digital features, not added physical strength.
Can I make a smart lock as secure as a deadbolt?
Physically, yes, if the smart lock upgrades a quality deadbolt and is installed correctly[1,2]. Digitally, security depends on the device’s software, how it is managed, and regular updates[3]. No lock is invulnerable, but careful setup and maintenance reduce risk.
How the numbers work
These figures were computed for this article, not estimated by its writer. Inputs come from the numbered sources or are assumptions, labelled as such; change an assumption and the results change with it.
| Figure | Value | Where it comes from |
|---|---|---|
| Distinct attack methods on deadbolts | 2 methods | source [2] |
| Distinct attack methods on smart locks | 2 methods | source [3] |
| Smart lock models tested in security study | 5 models | source [3] |
| Difference in primary attack methods | 0 methods | computed: Distinct attack methods on smart locks - Distinct attack methods on deadbolts |