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
Exploitability
AV:NAttack VectorNetwork
AC:HAttack ComplexityHigh
PR:NPrivileges RequiredNone
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:HConfidentialityHigh
I:NIntegrityNone
A:NAvailabilityNone
Weaknesses
Affected Products
gnupg
oss-projectaka libgcrypt, libksba
Werner Koch
oss-project·DE
АО «ИВК»
commercial·RUaka ivk
АО «НТЦ ИТ РОСА»
commercial·RU
and 2 more affected products View all →
Exploitability
Official Patch Available
Attack Graph
Products CVE Techniques Tactics
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MITRE ATT&CK
1 technique Collection
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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