alpine 3.6
crypto weakness #78

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:

wpa_supplicant/src/wpa_supplicant-2.6/src/crypto/aes-internal-dec.c

Context:

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

 		ROUND(0,s,t);
	}

#endif /* ?FULL_UNROLL */

#undef ROUND

	/*
	 * apply last round and
	 * map cipher state to byte array block:
	 */
	s0 = TD41(t0) ^ TD42(t3) ^ TD43(t2) ^ TD44(t1) ^ rk[0];
	PUTU32(pt     , s0);
	s1 = TD41(t1) ^ TD42(t0) ^ TD43(t3) ^ TD44(t2) ^ rk[1];
	PUTU32(pt +  4, s1);
	s2 = TD41(t2) ^ TD42(t1) ^ TD43(t0) ^ TD44(t3) ^ rk[2];
	PUTU32(pt +  8, s2);
	s3 = TD41(t3) ^ TD42(t2) ^ TD43(t1) ^ TD44(t0) ^ rk[3];
	PUTU32(pt + 12, s3);
}

void aes_decrypt(void *ctx, const u8 *crypt, u8 *plain)
{
	u32 *rk = ctx;
	rijndaelDecrypt(ctx, rk[AES_PRIV_NR_POS], crypt, plain);
}


void aes_decrypt_deinit(void *ctx)
{
	os_memset(ctx, 0, AES_PRIV_SIZE);
	os_free(ctx);
} 

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