CVE-2021-40528 (GCVE-0-2021-40528)

Vulnerability from cvelistv5 – Published: 2021-09-06 00:00 – Updated: 2025-06-09 15:13
VLAI
Summary
The ElGamal implementation in Libgcrypt before 1.9.4 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.
Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-06-09 15:12 UTC
CWE
  • n/a
  • CWE-327 - Use of a Broken or Risky Cryptographic Algorithm
Assigner
mitre CNA under the mitre root
CNA scorecard E 29/100 over 2159 records in the last 180 days details
References
Show details on NVD website
To clipboard 

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