Microchip submerged in liquid nitrogen, with ghostly data figures.

Unlocking Secrets: How Temperature Affects Your Device's Security

Theo Raines in Tech & Innovation August 2025 • 4 min read.

"Dive into the chilling truth about data remanence and its impact on the security of your devices, especially with SRAM PUFs, and learn how to protect your digital life."

In our increasingly digital world, the security of our personal devices is paramount. We rely on cryptographic keys to protect everything from our bank accounts to our personal emails. But what if the very hardware designed to safeguard these keys had a hidden vulnerability? Physical Unclonable Functions (PUFs) offer a unique approach to security by leveraging the inherent physical characteristics of a device. Among these, Static Random Access Memory (SRAM) PUFs have become popular for their efficiency and ease of integration.

SRAM PUFs use the unique startup values of SRAM cells to generate cryptographic keys. These values, resulting from minute manufacturing variations, are considered a device's unique fingerprint. However, environmental factors like temperature can significantly impact the reliability and security of SRAM PUFs. Understanding these effects is crucial for building robust security systems.

This article explores a chilling discovery: how low temperatures can compromise the security of SRAM PUFs through data remanence. We'll delve into the science behind this phenomenon, discuss a potential attack strategy, and offer practical countermeasures to protect your devices from these threats.

The Chilling Effect: Data Remanence Unveiled

Microchip submerged in liquid nitrogen, with ghostly data figures.

Data remanence, in simple terms, is the lingering presence of data on a storage medium even after it has been supposedly erased. Think of it like a faint echo of a previous recording on a tape. While this phenomenon has been studied in various contexts, its implications for SRAM PUFs at low temperatures are particularly concerning. Recent research has revealed that when SRAM modules are exposed to extremely low temperatures (between -110°C and -40°C), data remanence becomes significantly pronounced.

Why does this happen? At these temperatures, the electrical properties of the silicon change, making it harder to completely erase the data stored in the SRAM cells. This creates an opportunity for attackers to exploit this vulnerability and potentially recover sensitive information. What makes it alarming is that data remanence can persist even after standard erasure techniques are applied.

Here's why low-temperature data remanence is a serious concern:

Compromised Cryptographic Keys: Attackers can potentially recover the cryptographic keys generated by the SRAM PUF.
Bypass Security Measures: Standard erasure techniques may not be effective at these temperatures.
Increased Attack Surface: Opens up new avenues for exploiting device vulnerabilities.

Imagine a scenario where an attacker cools down a device containing an SRAM PUF to extremely low temperatures. They then power cycle the device and attempt to read the SRAM values. Due to data remanence, the attacker might be able to recover a significant portion of the original SRAM state, effectively cloning the device's cryptographic key. This opens the door to various malicious activities, including unauthorized access, data theft, and identity fraud.

Protecting Your Devices: Countermeasures and Future Directions

Fortunately, there are several potential countermeasures to mitigate the risks posed by low-temperature data remanence. One approach involves implementing more robust erasure techniques that are effective even at extremely low temperatures. Another strategy is to design SRAM modules that are less susceptible to data remanence. Furthermore, manufacturers can incorporate temperature sensors into devices to detect and respond to sudden temperature drops, potentially triggering security protocols that prevent unauthorized access to the SRAM.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1109/dsd.2018.00102, Alternate LINK

Title: Low-Temperature Data Remanence Attacks Against Intrinsic Sram Pufs

Journal: 2018 21st Euromicro Conference on Digital System Design (DSD)

Publisher: IEEE

Authors: Nikolaos Athanasios Anagnostopoulos, Tolga Arul, Markus Rosenstihl, Andre Schaller, Sebastian Gabmeyer, Stefan Katzenbeisser

Published: 2018-08-01

Everything You Need To Know

What is data remanence, and how does it impact the security of SRAM PUFs at low temperatures?

Data remanence refers to the persistence of data on a storage medium, such as an SRAM cell, even after an attempt to erase it. In the context of SRAM PUFs, low temperatures (between -110°C and -40°C) exacerbate this effect, making it harder to completely erase the stored data. This is because the electrical properties of the silicon change at these temperatures. Attackers could potentially exploit this vulnerability to recover sensitive information, even after standard erasure techniques are applied. Data remanence is like a faint echo of previous data, posing security risks, especially with SRAM PUFs at low temperatures.

What are SRAM PUFs, and how do they utilize a device's unique characteristics for security?

SRAM PUFs, or Static Random Access Memory Physical Unclonable Functions, leverage the unique startup values of SRAM cells to generate cryptographic keys. These startup values arise from minute manufacturing variations, creating a unique 'fingerprint' for each device. However, environmental factors such as temperature can compromise the reliability and security of SRAM PUFs. SRAM PUFs offer a unique security approach. They generate cryptographic keys by exploiting manufacturing variations within SRAM, but their susceptibility to environmental factors such as temperature poses critical security challenges.

How do low temperatures specifically affect the reliability and security of SRAM PUFs?

Low temperatures, specifically between -110°C and -40°C, affect SRAM PUFs by causing data remanence to become significantly more pronounced. At these temperatures, the electrical properties of silicon change, making it difficult to completely erase data stored in the SRAM cells. This allows attackers to potentially recover cryptographic keys generated by the SRAM PUF, even after standard erasure techniques have been applied. The chilling temperatures create a vulnerability. They alter silicon's electrical properties, making data erasure incomplete and posing security risks to SRAM PUFs.

What are some practical countermeasures to protect devices against low-temperature data remanence attacks targeting SRAM PUFs?

To protect devices from low-temperature data remanence attacks, several countermeasures can be implemented. More robust erasure techniques that are effective even at extremely low temperatures can be used. Designing SRAM modules that are less susceptible to data remanence is another strategy. Additionally, manufacturers can incorporate temperature sensors into devices to detect and respond to sudden temperature drops, potentially triggering security protocols that prevent unauthorized access to the SRAM. Using effective erasure and temperature sensing can protect SRAM PUFs.

What are the potential implications if an attacker successfully recovers cryptographic keys from an SRAM PUF using low-temperature data remanence?

If an attacker successfully recovers cryptographic keys from an SRAM PUF using low-temperature data remanence, it could lead to several severe security breaches. These include unauthorized access to sensitive data, data theft, identity fraud, and the ability to bypass existing security measures. By cloning a device's cryptographic key, an attacker could impersonate the device and gain unauthorized access to systems and networks. The attacker can clone a device's cryptographic key, leading to data theft and identity fraud.