CVE-2021-40530

published 2021-09-06

CVE-2021-40530: The ElGamal implementation in Crypto++ through 8.5 allows plaintext recovery because, during interaction between two cryptographic libraries, a certain…

Priority P4 30 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 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

5 ranges

Vendor	Product	Version range	Fixed in
cryptopp	crypto	<= 8.5	—
debian	libcrypto	< libcrypto++ 8.6.0-1 (bookworm)	libcrypto++ 8.6.0-1 (bookworm)
fedoraproject	fedora	—	—
fedoraproject	fedora	—	—
fedoraproject	fedora	—	—

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