alpine 3.6
access weakness #139


Weakness Breakdown


An access weakness occurs when software does not properly implement permissions that could have unintended consequences if exploited by malicious actors. An example of this weakness is when a default username and password are set by the developer but do not get changed by the system administrator.

Warning code(s):

Ensure that umask is given most restrictive possible setting.

File Name:



The highlighted line of code below is the trigger point of this particular Alpine 3.6 access weakness.

     for (i = 0; i < d->authNum; i++)
	if (auth[i]->name_length == 9 &&
	    memcmp(auth[i]->name, "SUN-DES-1", 9) == 0)
	if (auth[i]->name_length == 14 &&
	    memcmp(auth[i]->name, "MIT-KERBEROS-5", 14) == 0)
	XSetAuthorization (auth[i]->name, (int) auth[i]->name_length,
			   auth[i]->data, (int) auth[i]->data_length);

static int
openFiles (char *name, char *new_name, FILE **oldp, FILE **newp)
	mode_t	mask;
	int newfd;

	strcpy (new_name, name);
	strcat (new_name, "-n");
	 * Set safe umask for file creation operations.
	mask = umask (0077);
	 * Unlink the authorization file we intend to create, and then open
	 * it with O_CREAT | O_EXCL to avoid race-based symlink attacks.
	(void) unlink (new_name);
	newfd = open (new_name, O_WRONLY | O_CREAT | O_EXCL, 0600);
	if (newfd >= 0)
	    *newp = fdopen (newfd, "w");
	    LogError ("Cannot create file %s: %s\n", new_name,
		      _SysErrorMsg (errno));
	    *newp = NULL;
	 * There are no more attempts to create files after this point;
	 * restore the original umask.
	(void) umask (mask);
	if (!*newp) {
		Debug ("can't open new file %s\n", new_name);
		return 0;
	if (!*oldp)
	    *oldp = fopen (name, "r"); 

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