centos 7
crypto weakness #297

4

Weakness Breakdown


Definition:

This weakness involves creating non-standard or non-tested algorithms, using weak algorithms or applying cryptographic algorithms incorrectly. Algorithms that were once considered safe are commonly later found to be unsafe, as the algorithms were broken.

Warning code(s):

The crypt functions use a poor one-way hashing algorithm; since they only accept passwords of 8 characters or fewer and only a two-byte salt, they are excessively vulnerable to dictionary attacks given today's faster computing equipment.

File Name:

nss-softokn-3.36.0/nss/cmd/fipstest/fipstest.c

Context:

The highlighted line of code below is the trigger point of this particular Centos 7 crypto weakness.

         /* key3 independent */
        for (k = 16; k < 24; k++) {
            /* key3[i+1] = KEY3[i] xor PT/CT[j-2] */
            key[k] ^= text_2[k - 16];
        }
    }
    /* set the parity bits */
    for (k = 0; k < 24; k++) {
        key[k] = odd_parity(key[k]);
    }
}

/*
 * Perform the Monte Carlo Test
 *
 * mode = NSS_DES_EDE3 or NSS_DES_EDE3_CBC
 * crypt = ENCRYPT || DECRYPT
 * inputtext = plaintext or Cyphertext depending on the value of crypt
 * inputlength is expected to be size 8 bytes
 * iv = needs to be set for NSS_DES_EDE3_CBC mode
 * resp = is the output response file.
 */
void
tdea_mct_test(int mode, unsigned char *key, unsigned int numKeys,
              unsigned int crypt, unsigned char *inputtext,
              unsigned int inputlength, unsigned char *iv, FILE *resp)
{

    int i, j;
    unsigned char outputtext_1[8]; /* PT/CT[j-1] */
    unsigned char outputtext_2[8]; /* PT/CT[j-2] */
    char buf[80];                  /* holds one line from the input REQUEST file. */
    unsigned int outputlen;
    unsigned char outputtext[8];

    SECStatus rv;

    if (mode == NSS_DES_EDE3 && iv != NULL) {
        printf("IV must be NULL for NSS_DES_EDE3 mode");
        goto loser;
    } else if (mode == NSS_DES_EDE3_CBC && iv == NULL) {
        printf("IV must not be NULL for NSS_DES_EDE3_CBC mode");
        goto loser;
    }

    /* loop 400 times */
    for (i = 0; i < 400; i++) {
        /* if i == 0 CV[0] = IV  not necessary */
        /* record the count and key values and plainText */
        sprintf(buf, "COUNT = %d\n", i); 

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