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OWASP Top 10 Mobile Vulnerabilities | Cobalt

Written by Cobalt | Jul 30, 2026, 7:04:09 PM

OWASP Top 10 Mobile Vulnerabilities

Mobile apps now handle everything from banking transactions, healthcare records, and our social lives, making them prime targets for malicious hackers.

Yet mobile security often lags behind web application security, leaving organizations exposed in ways they may not even realize.

The OWASP Mobile Top 10 identifies the most critical security risks facing mobile applications today, offering development and security teams a shared framework for understanding where their apps are most vulnerable. Below, we break down each of the ten risks, how attackers exploit them, what causes them, and the concrete steps you can take to mitigate them.

1. Improper Credential Usage

This vulnerability occurs when attackers can use mishandled credentials to gain access to unauthorized functionality on target apps. For instance, an attacker might discover credentials by finding them in mobile app source code, intercepting them during transmissions between the app and its backend server-side infrastructure, or gaining physical access to a stolen device and extracting insecurely stored credentials. This can expose apps to data breaches, compromise of user privacy, fraud, and takeover of administrative functionality.

The threat of improper credential usage typically arises when credentials are hardcoded into app code or configuration files or when credentials are transmitted or stored insecurely. This risk can be avoided by:

  • Avoiding use of hardcoded credentials in app code and configuration files
  • Encrypting credentials in transit
  • Avoiding storage of credentials on devices by using secure, revocable access tokens
  • Using strong authentication protocols
  • Periodically updating and rotating used API keys and tokens

2. Inadequate Supply Chain Security

This risk stems from attacker's exploitation of insecurities in third-party libraries, software development kits, or APIs supplying app code or in vendor tools and processes. For example, an attacker might insert malicious code into a file with a name resembling a popular software package and upload it into a code repository in order to deceive developers into downloading it. Likewise, a developer might download software containing poor coding that leaves it susceptible to exploitation.

Inadequate supply chain security risks usually emerge from using insecure code repositories, following lax coding security practices during development, or failing to vet software vendors. Supply chain risks can be mitigated by:

  • Only using trusted and validated third-party sources
  • Following secure coding, code review, and testing practices during development
  • Applying security controls for app releases, patches, and updates
  • Implementing secure app signing and distribution processes
  • Using security scanning and testing to detect supply chain incidents

3. Insecure Authentication/Authorization

This risk represents vulnerability to attackers exploiting weak app authentication and authorization processes. For example, if an app does not verify that service requests from backend services are coming from known users, a hacker might submit a backend request and anonymously trigger functionality that affects authentic users. Alternately, hackers might bypass weak authentication controls to log in as legitimate users and then force-browse to discover hidden resources and access restricted functionality. These exploits usually are executed through mobile malware on devices or on botnets. This can result in access to escalated privileges, data theft, fraud, and reputation damage.

Insecure authentication and authorization risks reflect weak authentication patterns and inadequate reinforcement of security checks. This can be corrected by taking steps such as:

  • Matching mobile authentication requirements to web application equivalents
  • Performing authentication requests server-side or encrypting client-side data storage
  • Avoiding storage of credentials within “Remember Me” functionality
  • Using device-specific authentication tokens
  • Avoiding authentication values which are easy to spoof, such as geolocation
  • Requiring opt-in for persistent authentication
  • Avoiding use of four-digit PIN numbers for authentication
  • Using server-side controls to reinforce client-side authentication
  • Reinforcing local authentication and authorization checks with local integrity checks for unauthorized code changes
  • Using biometric checks to protect sensitive authentication data

4. Insufficient Input/Output Validation

This threat arises when external sources such as user inputs or network data can introduce unvalidated or unsanitized data. For example, an attacker might input a malicious command, create user-generated output that steals other users’ session cookies, or use malicious app output to hjjack a device and steal data. This vulnerability can allow unauthorized code execution, data breaches, system disruptions, and compromise of data integrity.

This category of risk stems from poor input and output validation practices, failure to apply context-specific validation, lack of data integrity checks, and insecure coding. Mitigation steps include:

  • Using strict techniques to validate and sanitize user input
  • Applying length restrictions to user input
  • Sanitizing output data
  • Encoding output data when being displayed or in transit
  • Performing context-specific validation checks for actions such as database queries and file uploads
  • Running data integrity checks
  • Following secure coding practices
  • Conducting regular code reviews and pentests

5. Insecure Communication

This risk occurs when hackers intercept data transmitted between devices and remote servers via carrier networks and the Internet. For example, if an app fails to inspect a certificate offered by a server, hackers may be able to intercept communications through a TLS proxy server. Insecure communications allow eavesdroppers to intercept and modify data, which can enable data theft and identity theft and set the stage for further attacks.

Insecure communication risks can emerge from shared networks, rogue carriers or network devices, or malware. Mitigation steps include:

  • Applying SSL/TLS to transport channels which transmit data to a backend APIs or web services
  • Using SSL versions of third-party providers such as analytics companies and social networks when running routines via browsers or webkits, while avoiding mixed SSL sessions
  • Implementing strong, standard cipher suites with adequate key lengths
  • Use certificates signed by trusted CA providers and refusing bad certificates
  • Adopting certificate pinning
  • Requiring SSL chain verification
  • Verifying endpoint server identity using trusted certificates in key chains before establishing secure connections
  • Alert users through UIs when apps detect invalid certificates
  • Avoiding sending sensitive data over alternate channels such as SMS or notifications
  • Applying separate layers of encryption to any sensitive data before sending it to SSL channels
  • Using self-signed certificates or local development certificate authorities during development cycles rather than overriding SSL verification methods to allow untrusted certificates
  • Conducting security analysis of application traffic to detect if traffic goes through plaintext channels
  • Following Android-specific and iOS-specific best practices for securing communication

6. Inadequate Privacy Controls

Poor privacy controls allow attackers to access personally identifiable information (PII) such as contact information, email and IP addresses, credit card data, or healthcare data. For example, unsanitized logs and error messages may reveal PII through publicly exposed files visible to users or platform providers. Attackers can use this type of data to impersonate users, perpetrate fraud, misuse payment data, or extort data owners.

Privacy controls can be strengthened through steps such as:

  • Avoiding collection of unnecessary data
  • Replacing critical data with less sensitive data, such as substituting coarse-grained geolocation data for fine-grained data
  • Reducing frequency of sensitive data collection, such as collecting geolocation data every hour instead of every minute
  • Anonymizing or blurring data through means such as hashing, bucketing, or noise insertion
  • Deleting data after a set period or after it is no longer needed
  • Allowing users to consent to optional PII usage
  • Using proper authentication and authorization for PII data in storage or in transit
  • Running threat modeling scenarios to identify app-specific risks and develop customized security procedures
  • Deploying static and dynamic security checking tools to identify risks such as logging of sensitive data, clipboard leakage, or insecure URL query parameters
  • Applying additional security measures for particularly critical data

7. Insufficient Binary Protections

This risk arises from inadequate protection of compiled code. For example, if a subscription-based app uses insufficiently secured app binaries containing hardcoded API keys, hackers could steal or sell the keys to bypass or intercept subscription fees. This vulnerability can cause financial loss, intellectual property theft, and reputational damage.

Binary protection compromise may reflect neglected obfuscation of sensitive data, failure to run integrity checks, lack of jailbreak detection, publication of apps in debugging mode, or reliance on client-side logic for security decisions. To mitigate this risk:

  • Obfuscate app binary
  • Require backend processes to enforce local security checks for protected features
  • Run integrity checks
  • Report detected redistribution of malicious code

8. Security Misconfiguration

This vulnerability results from improper configuration of security settings, permissions, or controls. For example, an app with insecure default settings can allow attackers to exploit insecure features to gain access to sensitive data or unauthorized functionality. Leaving this risk unfixed can result in data breaches, financial loss, regulatory fines, or reputation damage.

Security misconfigurations usually reflect insecure coding and configuration practices. Avoid this risk by:

  • Securing default settings and configurations to avoid exposing sensitive data or allowing excessive permissions
  • Avoiding hardcoded default credentials
  • Requesting only necessary permissions for running the app
  • Securing network configurations by disallowing cleartext traffic and using certificate pinning
  • Disabling debugging
  • Disabling backup mode in Android
  • Only exporting necessary activities, content providers, and services

9. Insecure Data Storage

This vulnerability involves failing to secure data at rest or in transit to storage. For example, storing passwords in plaintext in a local file can allow attackers who gain access to a device to retrieve them. Exploitations of this vulnerability can put organizations at risk of data breaches, user account compromise, data tampering, and compliance violations.

Insecure data storage exposure may result from weak encryption, poor data protection and data storage mechanisms, and mishandling of user credentials. Data storage vulnerabilities can be mitigated by steps such as:

  • Applying strong encryption to data at transit and at rest
  • Using secure data transmission protocols and channels
  • Deploying secure, device-specific storage mechanisms such as Android Keystore or iOS Keychain
  • Configure strong access controls
  • Validate input
  • Sanitize data
  • Adopt secure session management
  • Keep software dependencies updated and patched

10. Insufficient Cryptography

This vulnerability enables hackers to exploit insecure encryption and hash functions. For example, if an app uses an outdated encryption algorithm with known weaknesses, a man-in-the-middle attacker who has intercepted a transmission can decode encrypted data and modify it before it arrives at its destination. This vulnerability can trigger data breaches, intellectual property theft, financial losses, and compliance fines.

Insufficient cryptography risks typically stem from poor encryption or insecure hash functions. To mitigate vulnerability, take steps such as:

  • Using strong encryption algorithms
  • Requiring sufficient key length
  • Applying secure key management practices
  • Following standard encryption best practices and avoiding custom encryptions
  • Storing encryption keys securely
  • Using secure transport layer protocols
  • Validating and authenticating certificates and digital signatures
  • Keeping cryptographic updates and patches current
  • Implementing strong hash functions
  • Applying salting
  • Using key derivation functions
  • Pentesting cryptography vulnerabilities

The OWASP Mobile Top 10 isn't a checklist to complete once and file away. Many of these vulnerabilities share common roots: insecure coding practices, weak encryption, and misplaced trust in client-side controls. That means addressing them requires more than patching individual issues; it demands building security into how your teams design, develop, and ship mobile apps.

Regular pentesting plays a critical role here, surfacing the vulnerabilities that slip past code reviews and automated scans before attackers find them first. Start by assessing your mobile apps against these ten risks, prioritize the gaps that expose your most sensitive data, and make security testing a continuous practice rather than a pre-launch formality.