High severity · published Feb 7, 2018
CVE-2018-6829
cipher/elgamal.c in Libgcrypt through 1.8.2, when used to encrypt messages directly, improperly encodes plaintexts, which allows attackers to obtain sensitive information by…
7.5
CVSS
1.8%
EPSS
No
On KEV
Description
cipher/elgamal.c in Libgcrypt through 1.8.2, when used to encrypt messages directly, improperly encodes plaintexts, which allows attackers to obtain sensitive information by reading ciphertext data (i.e., it does not have semantic security in face of a ciphertext-only attack). The Decisional Diffie-Hellman (DDH) assumption does not hold for Libgcrypt's ElGamal implementation.
CVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.8% · higher than 78% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
Libgcrypt · Gnupg
through 1.8.2 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2018-6829
CVE.org
https://www.cve.org/CVERecord?id=CVE-2018-6829
Third Party Advisory
https://github.com/weikengchen/attack-on-libgcrypt-elgamal
Exploit
https://github.com/weikengchen/attack-on-libgcrypt-elgamal/wiki
Issue Tracking
https://lists.gnupg.org/pipermail/gcrypt-devel/2018-February/004394.html
www.oracle.com
https://www.oracle.com/security-alerts/cpujan2020.html
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