Cipher Block Chaining (CBC) mode
E845073
Cipher Block Chaining (CBC) mode is a block cipher operation method that enhances confidentiality by XORing each plaintext block with the previous ciphertext block before encryption, making each block’s encryption dependent on all preceding blocks.
All labels observed (4)
| Label | Occurrences |
|---|---|
| AES-CBC | 1 |
| CBC (Cipher Block Chaining) | 1 |
| Cipher Block Chaining (CBC) mode canonical | 1 |
| Cipher Block Chaining mode | 1 |
How this entity was disambiguated
This entity first appeared as the object of triple T10157691 — resolving that mention is where its identity was fixed. The disambiguator weighed these candidate entities and picked the highlighted one (or “None”, minting a new entity). This is how homonymy is resolved: the same surface form can point to different entities.
NED1
Entity disambiguation (via context triple)
gpt-5-mini-2025-08-07
Target entity: Cipher Block Chaining (CBC) mode Context triple: [NIST SP 800-38A, modeDefined, Cipher Block Chaining (CBC) mode]
-
A.
CBC-DES
CBC-DES is a cryptographic privacy protocol that uses the Data Encryption Standard in Cipher Block Chaining mode to provide confidentiality for SNMPv3 messages.
-
B.
CBC-MAC
CBC-MAC (Cipher Block Chaining Message Authentication Code) is a cryptographic technique that uses a block cipher in CBC mode to generate a fixed-size tag for ensuring data integrity and authenticity.
-
C.
AES-CTR
AES-CTR is a widely used symmetric-key encryption mode that turns the AES block cipher into a fast, parallelizable stream cipher by encrypting successive counter values and XORing them with the plaintext.
-
D.
OCB authenticated-encryption mode
OCB authenticated-encryption mode is a block cipher mode of operation that simultaneously provides data confidentiality and integrity with high efficiency and minimal overhead.
-
E.
Serpent cipher
Serpent cipher is a symmetric-key block cipher and former AES finalist known for its strong security margin and conservative design based on a substitution–permutation network structure.
- F. None of above. chosen
- G. Unsure - the case is ambiguous/there is not enough information to decide.
NED2
Entity disambiguation (via description)
gpt-5-mini-2025-08-07
Target entity: Cipher Block Chaining (CBC) mode Target entity description: Cipher Block Chaining (CBC) mode is a block cipher operation method that enhances confidentiality by XORing each plaintext block with the previous ciphertext block before encryption, making each block’s encryption dependent on all preceding blocks.
-
A.
CBC-DES
CBC-DES is a cryptographic privacy protocol that uses the Data Encryption Standard in Cipher Block Chaining mode to provide confidentiality for SNMPv3 messages.
-
B.
CBC-MAC
CBC-MAC (Cipher Block Chaining Message Authentication Code) is a cryptographic technique that uses a block cipher in CBC mode to generate a fixed-size tag for ensuring data integrity and authenticity.
-
C.
AES-CTR
AES-CTR is a widely used symmetric-key encryption mode that turns the AES block cipher into a fast, parallelizable stream cipher by encrypting successive counter values and XORing them with the plaintext.
-
D.
OCB authenticated-encryption mode
OCB authenticated-encryption mode is a block cipher mode of operation that simultaneously provides data confidentiality and integrity with high efficiency and minimal overhead.
-
E.
Serpent cipher
Serpent cipher is a symmetric-key block cipher and former AES finalist known for its strong security margin and conservative design based on a substitution–permutation network structure.
- F. None of above. chosen
Statements (50)
| Predicate | Object |
|---|---|
| instanceOf |
block cipher mode of operation
ⓘ
encryption mode ⓘ |
| abbreviation | CBC ⓘ |
| blockIndexNotation |
C_i = E_K(P_i XOR C_{i-1})
ⓘ
P_i = D_K(C_i) XOR C_{i-1} ⓘ |
| category | chaining mode ⓘ |
| commonlyUsedWith |
3DES
ⓘ
AES ⓘ |
| commonlyUses | PKCS#7 padding ⓘ |
| decryptionStep |
XOR decrypted block with previous ciphertext block
ⓘ
decrypt ciphertext block with block cipher ⓘ |
| discouragedIn | modern protocol designs without AEAD ⓘ |
| doesNotProvide |
authentication
ⓘ
integrity ⓘ |
| encryptionStep |
XOR plaintext block with previous ciphertext block
ⓘ
encrypt XOR result with block cipher ⓘ |
| errorPropagationLength | two blocks ⓘ |
| firstBlockDecryptionUses | initialization vector ⓘ |
| firstBlockXORedWith | initialization vector ⓘ |
| firstCiphertextBlockNotation | C_0 = E_K(P_0 XOR IV) ⓘ |
| introducedIn | 1976 ⓘ |
| IVLength | block size of underlying cipher ⓘ |
| notRecommendedFor | high-throughput low-latency network encryption without hardware support ⓘ |
| operatesOn | fixed-size blocks ⓘ |
| parallelizable |
no for encryption
ⓘ
yes for decryption ⓘ |
| primaryGoal | confidentiality ⓘ |
| property |
each ciphertext block depends on all previous plaintext blocks
ⓘ
error propagation to next block on bit error in ciphertext ⓘ identical plaintext blocks encrypt to different ciphertext blocks if IV differs ⓘ |
| publishedIn | NIST SP 800-38A ⓘ |
| replacedByInManyProtocols |
Galois/Counter Mode
ⓘ
linked to:
AES-GCM
|
| requires |
initialization vector
ⓘ
padding for non-multiple-of-block-size plaintexts ⓘ secret key ⓘ sequential processing of blocks for encryption ⓘ unique IV per key-stream ⓘ unpredictable IV ⓘ |
| securityDependsOn |
IV generation method
ⓘ
underlying block cipher strength ⓘ |
| standardizedBy | NIST ⓘ |
| suitableFor |
data at rest encryption
ⓘ
file encryption ⓘ |
| supports | confidentiality only ⓘ |
| usedInPastBy |
IPsec
ⓘ
TLS ⓘ |
| uses | block cipher ⓘ |
| vulnerableIf |
IV is predictable
ⓘ
IV is reused with same key and first block plaintext is related ⓘ |
| vulnerableTo | padding oracle attacks ⓘ |
How these facts were elicited
The pipeline generated the facts above by prompting gpt-5.1 with this entity's name + description and the instruction below.
Instruction
You are a knowledge base construction expert. Given a subject entity and a description of it, return factual statements that you know for the subject as a JSON list of dictionaries(triples), where keys must be "subject", "predicate" and "object". The number of facts may be very high, between 25 to 50 or more, for very popular subjects. For less popular subjects, the number of facts can be very low, like 5 or 10. # Requirements - If you don't know the subject at all, return an empty list. - If the subject is not a named entity, return an empty list. - Include at least one triple where predicate is "instanceOf". - Do not get too wordy. - Separate several objects into multiple triples with one object.
Input
Subject: Cipher Block Chaining (CBC) mode Description of subject: Cipher Block Chaining (CBC) mode is a block cipher operation method that enhances confidentiality by XORing each plaintext block with the previous ciphertext block before encryption, making each block’s encryption dependent on all preceding blocks.
Referenced by (4)
Full triples — surface form annotated when it differs from this entity's canonical label.
linked to: Cipher Block Chaining (CBC) mode
Recommendation for Block Cipher Modes of Operation: Methods and Techniques
→
standardizes
→
Cipher Block Chaining mode
ⓘ
linked to: Cipher Block Chaining (CBC) mode
linked to: Cipher Block Chaining (CBC) mode