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C

C static code analysis

Unique rules to find Bugs, Vulnerabilities, Security Hotspots, and Code Smells in your C code

  • All rules 315
  • Vulnerability13
  • Bug76
  • Security Hotspot19
  • Code Smell207

  • Quick Fix 19
Filtered: 59 rules found
cwe
    Impact
      Clean code attribute
        1. Function-like macros should not be invoked without all of their arguments

           Bug
        2. Function exit paths should have appropriate return values

           Bug
        3. The number of arguments passed to a function should match the number of parameters

           Bug
        4. Non-empty statements should change control flow or have at least one side-effect

           Bug
        5. Bitwise operators should not be applied to signed operands

           Bug
        6. Limited dependence should be placed on operator precedence

           Code Smell
        7. Variables should be initialized before use

           Bug
        8. Hard-coded secrets are security-sensitive

           Security Hotspot
        9. "sprintf" should not be used

           Security Hotspot
        10. Changing working directories without verifying the success is security-sensitive

           Security Hotspot
        11. Setting capabilities is security-sensitive

           Security Hotspot
        12. Accessing files should not introduce TOCTOU vulnerabilities

           Vulnerability
        13. Account validity should be verified when authenticating users with PAM

           Vulnerability
        14. Using "tmpnam", "tmpnam_s" or "tmpnam_r" is security-sensitive

           Security Hotspot
        15. Using "strncpy" or "wcsncpy" is security-sensitive

           Security Hotspot
        16. Using "strncat" or "wcsncat" is security-sensitive

           Security Hotspot
        17. Using "strcat" or "wcscat" is security-sensitive

           Security Hotspot
        18. Using "strlen" or "wcslen" is security-sensitive

           Security Hotspot
        19. Changing directories improperly when using "chroot" is security-sensitive

           Security Hotspot
        20. Using "strcpy" or "wcscpy" is security-sensitive

           Security Hotspot
        21. "memset" should not be used to delete sensitive data

           Vulnerability
        22. POSIX functions should not be called with arguments that trigger buffer overflows

           Vulnerability
        23. Cipher algorithms should be robust

           Vulnerability
        24. Encryption algorithms should be used with secure mode and padding scheme

           Vulnerability
        25. Server hostnames should be verified during SSL/TLS connections

           Vulnerability
        26. "pthread_mutex_t" should not be locked when already locked, or unlocked when already unlocked

           Bug
        27. Using publicly writable directories is security-sensitive

           Security Hotspot
        28. Using clear-text protocols is security-sensitive

           Security Hotspot
        29. Blocking functions should not be called inside critical sections

           Code Smell
        30. Expanding archive files without controlling resource consumption is security-sensitive

           Security Hotspot
        31. Server certificates should be verified during SSL/TLS connections

           Vulnerability
        32. Using weak hashing algorithms is security-sensitive

           Security Hotspot
        33. Cryptographic keys should be robust

           Vulnerability
        34. Weak SSL/TLS protocols should not be used

           Vulnerability
        35. Dynamically allocated memory should be released

           Bug
        36. Freed memory should not be used

           Bug
        37. Memory locations should not be released more than once

           Bug
        38. Memory access should be explicitly bounded to prevent buffer overflows

           Bug
        39. Zero should not be a possible denominator

           Bug
        40. "sizeof" should not be called on pointers

           Bug
        41. XML parsers should not be vulnerable to XXE attacks

           Vulnerability
        42. Multiline blocks should be enclosed in curly braces

           Code Smell
        43. "nonnull" parameters and return values of "returns_nonnull" functions should not be null

           Bug
        44. Setting loose POSIX file permissions is security-sensitive

           Security Hotspot
        45. Conditionally executed code should be reachable

           Bug
        46. Null pointers should not be dereferenced

           Bug
        47. Using pseudorandom number generators (PRNGs) is security-sensitive

           Security Hotspot
        48. Resources should be closed

           Bug
        49. Hard-coded passwords are security-sensitive

           Security Hotspot
        50. Code annotated as deprecated should not be used

           Code Smell
        51. Unused assignments should be removed

           Code Smell
        52. All code should be reachable

           Bug
        53. "switch" statements should have "default" clauses

           Code Smell
        54. Switch cases should end with an unconditional "break" statement

           Code Smell
        55. Track uses of "TODO" tags

           Code Smell
        56. Track uses of "FIXME" tags

           Code Smell
        57. Assignments should not be made from within conditions

           Code Smell
        58. Insecure functions should not be used

           Vulnerability
        59. "scanf()" and "fscanf()" format strings should specify a field width for the "%s" string placeholder

           Vulnerability

        Cryptographic keys should be robust

        responsibility - trustworthy
        security
        Vulnerability
        • cwe
        • privacy

        This vulnerability exposes encrypted data to attacks whose goal is to recover the plaintext.

        Why is this an issue?

        How can I fix it?

        More Info

        Encryption algorithms are essential for protecting sensitive information and ensuring secure communications in a variety of domains. They are used for several important reasons:

        • Confidentiality, privacy, and intellectual property protection
        • Security during transmission or on storage devices
        • Data integrity, general trust, and authentication

        When selecting encryption algorithms, tools, or combinations, you should also consider two things:

        1. No encryption is unbreakable.
        2. The strength of an encryption algorithm is usually measured by the effort required to crack it within a reasonable time frame.

        In today’s cryptography, the length of the key directly affects the security level of cryptographic algorithms.

        Note that depending on the algorithm, the term key refers to a different mathematical property. For example:

        • For RSA, the key is the product of two large prime numbers, also called the modulus.
        • For AES and Elliptic Curve Cryptography (ECC), the key is only a sequence of randomly generated bytes.
          • In some cases, AES keys are derived from a master key or a passphrase using a Key Derivation Function (KDF) like PBKDF2 (Password-Based Key Derivation Function 2)

        If an application uses a key that is considered short and insecure, the encrypted data is exposed to attacks aimed at getting at the plaintext.

        In general, it is best practice to expect a breach: that a user or organization with malicious intent will perform cryptographic attacks on this data after obtaining it by other means.

        What is the potential impact?

        After retrieving encrypted data and performing cryptographic attacks on it on a given timeframe, attackers can recover the plaintext that encryption was supposed to protect.

        Depending on the recovered data, the impact may vary.

        Below are some real-world scenarios that illustrate the potential impact of an attacker exploiting the vulnerability.

        Additional attack surface

        By modifying the plaintext of the encrypted message, an attacker may be able to trigger additional vulnerabilities in the code. An attacker can further exploit a system to obtain more information.
        Encrypted values are often considered trustworthy because it would not be possible for a third party to modify them under normal circumstances.

        Breach of confidentiality and privacy

        When encrypted data contains personal or sensitive information, its retrieval by an attacker can lead to privacy violations, identity theft, financial loss, reputational damage, or unauthorized access to confidential systems.

        In this scenario, the company, its employees, users, and partners could be seriously affected.

        The impact is twofold, as data breaches and exposure of encrypted data can undermine trust in the organization, as customers, clients and stakeholders may lose confidence in the organization’s ability to protect their sensitive data.

        Legal and compliance issues

        In many industries and locations, there are legal and compliance requirements to protect sensitive data. If encrypted data is compromised and the plaintext can be recovered, companies face legal consequences, penalties, or violations of privacy laws.

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