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CVE-2021-40528

Published: Sep 6, 2021Updated: Jun 9, 2025 Sources: CVE List NVD BDUCWE-327
5.9MEDIUM
NVD MITRE
EPSS Score
1.4%
Top 29.7%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

Description

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:HPR:NUI:NS:UC:HI:NA:N
Exploitability
AV:NAttack Vector
Network
AC:HAttack Complexity
High
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:NIntegrity
None
A:NAvailability
None
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Weaknesses

CWE-327

Affected Products

gnupg
oss-projectaka libgcrypt, libksba
libgcryptLibraryLibrary
Security Products / pki-crypto
ФССП России
RU
ОС ТД АИС ФССП РоссииOn-prem
Operating Systems / linux-distro
Werner Koch
oss-project·DE
LibgcryptLibrary
OSS Libraries / generic-library
АО «ИВК»
commercial·RUaka ivk
АЛЬТ СП 10On-premOS
Operating Systems / linux-distro
АО «НТЦ ИТ РОСА»
commercial·RU
ROSA VirtualizationOn-prem
Operating Systems / linux-distro
and 2 more affected products View all →

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique
Collection
View detailed technique mapping

References

https://eprint.iacr.org/2021/923
eprint.iacr.org
https://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git%3Ba=commit%3Bh=3462280f2e23e16adf3ed5176e0f2413d8861320
git.gnupg.org
https://ibm.github.io/system-security-research-updates/2021/07/20/insecurity-elgamal-pt1
ibm.github.io
and 8 more references View all →

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