alpine 3.6
access weakness #487


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.

     u = umask(0000);
    reset_umask = 1;

    if (mkdir(AVAHI_DAEMON_RUNTIME_DIR, 0755) < 0 && errno != EEXIST) {
        avahi_log_error("mkdir(\""AVAHI_DAEMON_RUNTIME_DIR"\"): %s", strerror(errno));
        goto fail;

    chown(AVAHI_DAEMON_RUNTIME_DIR, pw->pw_uid, gr->gr_gid);

    if (stat(AVAHI_DAEMON_RUNTIME_DIR, &st) < 0) {
        avahi_log_error("stat(): %s\n", strerror(errno));
        goto fail;

    if (!S_ISDIR(st.st_mode) || st.st_uid != pw->pw_uid || st.st_gid != gr->gr_gid) {
        avahi_log_error("Failed to create runtime directory "AVAHI_DAEMON_RUNTIME_DIR".");
        goto fail;

    r = 0;

    if (reset_umask)
    return r;

static void set_one_rlimit(int resource, rlim_t limit, const char *name) {
    struct rlimit rl;
    rl.rlim_cur = rl.rlim_max = limit;

    if (setrlimit(resource, &rl) < 0)
        avahi_log_warn("setrlimit(%s, {%u, %u}) failed: %s", name, (unsigned) limit, (unsigned) limit, strerror(errno));

static void enforce_rlimits(void) {
#ifdef RLIMIT_AS
    if (config.rlimit_as_set)
        set_one_rlimit(RLIMIT_AS, config.rlimit_as, "RLIMIT_AS");
    if (config.rlimit_core_set)
        set_one_rlimit(RLIMIT_CORE, config.rlimit_core, "RLIMIT_CORE");
    if (config.rlimit_data_set)
        set_one_rlimit(RLIMIT_DATA, config.rlimit_data, "RLIMIT_DATA");
    if (config.rlimit_fsize_set)
        set_one_rlimit(RLIMIT_FSIZE, config.rlimit_fsize, "RLIMIT_FSIZE");
    if (config.rlimit_nofile_set)
        set_one_rlimit(RLIMIT_NOFILE, config.rlimit_nofile, "RLIMIT_NOFILE");
    if (config.rlimit_stack_set) 

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