CVE-2021-40529

published 2021-09-06

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…

Priority P4 32 medium 5.9 CVSS 3.1

AV N AC H PR N UI N S U C H I N A N

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.

Affected

7 ranges

Vendor	Product	Version range	Fixed in
botan_project	botan	<= 2.18.1	—
botan_project	botan	>= 0 < 2.18.1+dfsg-3	2.18.1+dfsg-3
botan_project	botan	>= 0 < 2.18.1+dfsg-3	2.18.1+dfsg-3
debian	botan	< botan 2.18.1+dfsg-3 (bookworm)	botan 2.18.1+dfsg-3 (bookworm)
fedoraproject	fedora	—	—
fedoraproject	fedora	—	—
mozilla	thunderbird	< 91.12.0	91.12.0

CVSS provenance

nvd v3.1 5.9 MEDIUM CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

nvd v2.0 2.6 LOW AV:N/AC:H/Au:N/C:P/I:N/A:N

osv 5.9 MEDIUM

vendor_debian 5.9 MEDIUM

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CWE-327