Vulnerability in Botan Project

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 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.

Vulnerability class: POODLE (CVE-2014-3566)

EPSS: 0.015 (72.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-40529?
CVE-2021-40529 is a medium-severity vulnerability in Botan Project, classified under Use of a Broken or Risky Cryptographic Algorithm. CVSS score: 5.9/10. Published 2021-09-06.
How severe is CVE-2021-40529?
Medium severity. CVSS v3 base score is 5.9 out of 10.