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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 420
  • Vulnerability14
  • Bug111
  • Security Hotspot19
  • Code Smell276

  • Quick Fix 27
Filtered: 66 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. Function pointers should not be converted to any other type

           Bug
        8. Variables should be initialized before use

           Bug
        9. Hard-coded secrets are security-sensitive

           Security Hotspot
        10. "sprintf" should not be used

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

           Security Hotspot
        12. Setting capabilities is security-sensitive

           Security Hotspot
        13. Accessing files should not introduce TOCTOU vulnerabilities

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

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

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

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

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

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

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

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

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

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

           Vulnerability
        24. Relational and subtraction operators should not be used with pointers to different arrays

           Bug
        25. Cipher algorithms should be robust

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

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

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

           Bug
        29. Using publicly writable directories is security-sensitive

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

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

           Code Smell
        32. Dereferenced null pointers should not be bound to references

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

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

           Vulnerability
        35. Using weak hashing algorithms is security-sensitive

           Security Hotspot
        36. Cryptographic keys should be robust

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

           Vulnerability
        38. Dynamically allocated memory should be released

           Bug
        39. Freed memory should not be used

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

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

           Bug
        42. Zero should not be a possible denominator

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

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

           Vulnerability
        45. Multiline blocks should be enclosed in curly braces

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

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

           Security Hotspot
        48. Conditionally executed code should be reachable

           Bug
        49. Null pointers should not be dereferenced

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

           Security Hotspot
        51. Resources should be closed

           Bug
        52. Hard-coded passwords are security-sensitive

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

           Code Smell
        54. Unused assignments should be removed

           Code Smell
        55. All code should be reachable

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

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

           Code Smell
        58. Track uses of "TODO" tags

           Code Smell
        59. Track uses of "FIXME" tags

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

           Code Smell
        61. Insecure functions should not be used

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

           Vulnerability
        63. The value of an object must not be read before it has been set

           Bug
        64. Subtraction between pointers shall only be applied to pointers that address elements of the same array

           Bug
        65. A value should not be "unnecessarily written" to a local object

           Code Smell
        66. A function shall not contain "unreachable" statements

           Bug

        Server certificates should be verified during SSL/TLS connections

        responsibility - trustworthy
        security
        Vulnerability
        • cwe
        • symbolic-execution
        • full-project
        • privacy
        • cert
        • ssl

        This vulnerability makes it possible that an encrypted communication is intercepted.

        Why is this an issue?

        How can I fix it?

        More Info

        Transport Layer Security (TLS) provides secure communication between systems over the internet by encrypting the data sent between them. Certificate validation adds an extra layer of trust and security to this process to ensure that a system is indeed the one it claims to be.

        When certificate validation is disabled, the client skips a critical security check. This creates an opportunity for attackers to pose as a trusted entity and intercept, manipulate, or steal the data being transmitted.

        What is the potential impact?

        Establishing trust in a secure way is a non-trivial task. When you disable certificate validation, you are removing a key mechanism designed to build this trust in internet communication, opening your system up to a number of potential threats.

        Identity spoofing

        If a system does not validate certificates, it cannot confirm the identity of the other party involved in the communication. An attacker can exploit this by creating a fake server and masquerading as a legitimate one. For example, they might set up a server that looks like your bank’s server, tricking your system into thinking it is communicating with the bank. This scenario, called identity spoofing, allows the attacker to collect any data your system sends to them, potentially leading to significant data breaches.

        Loss of data integrity

        When TLS certificate validation is disabled, the integrity of the data you send and receive cannot be guaranteed. An attacker could modify the data in transit, and you would have no way of knowing. This could range from subtle manipulations of the data you receive to the injection of malicious code or malware into your system. The consequences of such breaches of data integrity can be severe, depending on the nature of the data and the system.

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