Eccouncil Exam 212-81 Topic 13 Question 56 Discussion

Actual exam question for Eccouncil's 212-81 exam

Question #: 56
Topic #: 13

Cryptographic hashes are often used for message integrity and password storage. It is important to understand the common properties of all cryptographic hashes. What is not true about a hash?

AFew collisions

BReversible

CVariable length input

DFixed length output

Show Suggested Answer

Suggested Answer: B

Reversible

https://en.wikipedia.org/wiki/Hash_function

Hash functions are not reversible.

Incorrect answers:

Fixed length output and Variable length input. Hash function receive variable length input and produce fixed length output

Few collisions. Every hash function with more inputs than outputs will necessarily have collisions

by Jacquelyne at May 05, 2025, 09:04 AM

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Theron

1 months ago

Ooh, B) Reversible? Sounds like a magic trick, not a cryptographic hash. I'll pass on that one.

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Reiko

9 days ago

User 3: D) Fixed length output is also a common property of cryptographic hashes.

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Miles

21 days ago

User 2: Miles is correct, collisions can happen with hashes.

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Blondell

23 days ago

Yeah, a reversible hash defeats the purpose of hashing in the first place.

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Blondell

28 days ago

I agree, a reversible hash doesn't sound secure at all.

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Dawne

29 days ago

User 1: A) Few collisions is not true about a hash.

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Lelia

2 months ago

Haha, B) Reversible? What is this, amateur hour? Hashes are all about that irreversible goodness, baby!

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Wilburn

29 days ago

D) Fixed length output

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Lorenza

1 months ago

C) Variable length input

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Mayra

2 months ago

A) Few collisions

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Laine

2 months ago

Yes, B is the correct answer. Cryptographic hashes are not reversible, making them secure for password storage.

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Dalene

2 months ago

I agree with Ceola, cryptographic hashes are designed to be one-way functions.

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Ceola

3 months ago

I think B is not true because cryptographic hashes are not reversible.

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Dudley

3 months ago

Definitely B) Reversible. That's like the opposite of what a hash is supposed to do. Might as well just store the original message!

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Chana

1 months ago

That's right, B) Reversible is definitely not a property of a cryptographic hash.

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Trinidad

1 months ago

Exactly, B) Reversible defeats the purpose of using a hash for security.

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Willard

1 months ago

Agreed, B) Reversible is not true. A hash should not be reversible.

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Jenise

1 months ago

D) Fixed length output

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Vilma

2 months ago

C) Variable length input

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Pamella

2 months ago

B) Reversible

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Virgina

2 months ago

A) Few collisions

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Lorrine

3 months ago

B) Reversible

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Hester

3 months ago

B) Reversible? That's a big no-no for a secure hash! Hashes are supposed to be one-way, not reversible.

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Justine

1 months ago

B) Reversible is not true about a hash.

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Georgene

1 months ago

Reversible? That's a big no-no for a secure hash! Hashes are supposed to be one-way, not reversible.

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Fidelia

1 months ago

D) Fixed length output

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Shantell

2 months ago

C) Variable length input

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Anissa

2 months ago

B) Reversible

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Craig

2 months ago

A) Few collisions

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