MEDIUM · 5.9

CVE-2021-40529

The ElGamal implementation in Botan through 2.18.1, as used in Thunderbird and other products, allows plaintext recovery because, during interaction between two cryptographic libraries, a certain dang...

Vulnerability Description

The ElGamal implementation in Botan through 2.18.1, as used in Thunderbird and other products, 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.

CVSS Score

5.9

MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack Vector
NETWORK
Attack Complexity
HIGH
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE

Affected Products

VendorProductVersions
Botan ProjectBotan<= 2.18.1
FedoraprojectFedora34
MozillaThunderbird< 91.12.0

Related Weaknesses (CWE)

References

FAQ

What is CVE-2021-40529?

CVE-2021-40529 is a vulnerability with a CVSS score of 5.9 (MEDIUM). The ElGamal implementation in Botan through 2.18.1, as used in Thunderbird and other products, allows plaintext recovery because, during interaction between two cryptographic libraries, a certain dang...

How severe is CVE-2021-40529?

CVE-2021-40529 has been rated MEDIUM with a CVSS base score of 5.9/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2021-40529?

Check the references section above for vendor advisories and patch information. Affected products include: Botan Project Botan, Fedoraproject Fedora, Mozilla Thunderbird.