alpine 3.6
access weakness #484


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.

static int save_address(const char *fn, uint32_t addr) {
    FILE *f;
    char buf[32];
    mode_t u;


    u = umask(0033);
    if (!(f = fopen(fn, "w"))) {
        daemon_log(LOG_ERR, "fopen() failed: %s", strerror(errno));
        goto fail;

    fprintf(f, "%s\n", inet_ntop(AF_INET, &addr, buf, sizeof (buf)));

    return 0;

    if (f)


    return -1;

 * Allocate a buffer with two pointers in front, one of which is
 * guaranteed to point ETHER_HDR_SIZE bytes into it.
static ArpPacket* packet_new(size_t packet_len) {
    ArpPacket *p;
    uint8_t *b;

    assert(packet_len > 0);

#ifdef __linux__
    b = avahi_new0(uint8_t, sizeof(struct ArpPacket) + packet_len);
    p = (ArpPacket*) b;
    p->ether_header = NULL;
    p->ether_payload = b + sizeof(struct ArpPacket);

    b = avahi_new0(uint8_t, sizeof(struct ArpPacket) + ETHER_HDR_SIZE + packet_len);
    p = (ArpPacket*) b;
    p->ether_header = b + sizeof(struct ArpPacket);
    p->ether_payload = b + sizeof(struct ArpPacket) + ETHER_HDR_SIZE; 

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