CVE-2021-40530: Medium severity Cryptopp Crypto\+\+ vulnerability

Published Sep 6, 2021
·
Updated

The ElGamal implementation in Crypto++ through 8.5 allows plaintext recovery because, during interaction between two cryptographic libraries, a certain dangerous combination of the prime defined by the receiver's public key, the generator defined by the receiver's public key, and the sender's ephemeral exponents can lead to a cross-configuration attack against OpenPGP.

Affected Software

4 affected components
Cryptopp Crypto\+\+<=8.5
Fedoraproject Fedora=33
Fedoraproject Fedora=34
Fedoraproject Fedora=35

Event History

Sep 6, 2021
CVE Published
via MITRE·06:44 PM
Data Sourced
via MITRE·06:44 PM
Description
Data Sourced
via NVD·07:15 PM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is CVE-2021-40530?

CVE-2021-40530 is a vulnerability in the ElGamal implementation in Crypto++ through version 8.5.

2

How does CVE-2021-40530 allow plaintext recovery?

CVE-2021-40530 allows plaintext recovery due to a certain dangerous combination of parameters during interaction between cryptographic libraries.

3

Which software is affected by CVE-2021-40530?

The affected software includes Crypto++ versions up to and including 8.5, as well as Fedora versions 33, 34, and 35.

4

What is the severity of CVE-2021-40530?

CVE-2021-40530 has a severity rating of 5.9, which is considered medium.

5

How can I find more information about CVE-2021-40530?

You can find more information about CVE-2021-40530 on the following references: [Reference 1](https://eprint.iacr.org/2021/923), [Reference 2](https://ibm.github.io/system-security-research-updates/2021/07/20/insecurity-elgamal-pt1), [Reference 3](https://ibm.github.io/system-security-research-updates/2021/09/06/insecurity-elgamal-pt2).

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