TI-2018-04986 Aliases CVE-2018-6829 GHSA-wcf7-2f92-j5mv

cipher/elgamal.c in Libgcrypt through 1.8.2, when used to encrypt messages directly…

LOW 36CWE-327Published 2018-02-07 · Updated 2024-08-05

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Information disclosure
Confidentiality · integrity · availability: High · None · None
Fix status: No fix listed

Attack profile from CVSS 3.0 · NVD. Fix status from CNA. Impact type from CWE-327.

Summary

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.

Why it matters now

EPSS 0.01777 78th percentileScored 2026-11-07

Public exploit Yes 1 exploit referenceTagged by NVD

Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
—	—	all versions	—	No fix listed	CNA

— Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:gnupg:libgcrypt::::::::	up to 1.8.2	Vulnerable	GnuPG

cpe:2.3:a:gnupg:libgcrypt:*:*:*:*:*:*:*:* Versions up to 1.8.2 Vulnerable ·GnuPG

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

Not affected: 4 products

Red Hat Enterprise Linux 5
Red Hat Enterprise Linux 6
Red Hat Enterprise Linux 7
Red Hat Enterprise Linux 8

Timeline

2026-10-02 Threatist record created from CVE-2018-6829
2026-10-03 Alias added: GHSA-wcf7-2f92-j5mv

References

Exploit 1

https://github.com/weikengchen/attack-on-libgcrypt-elgamal/wiki

Advisory 2

Other 1

https://www.oracle.com/security-alerts/cpujan2020.html

TI-2021-12953 Libgcrypt before 1.8.8 and 1.9.x before 1.9.3 mishandles ElGamal encryption because it… CVSS 3.1HIGH 7.5
TI-2017-00354 Information disclosure in libgcrypt CVSS 3.0HIGH 7.5
TI-2017-05168 Information disclosure in GnuPG libgcrypt CVSS 3.0MEDIUM 6.8
TI-2021-02343 _gcry_md_block_write in cipher/hash-common.c in Libgcrypt version 1.9.0 has a heap-based… CVSS 3.1HIGH 7.8
TI-2019-09661 In Libgcrypt 1.8.4, the C implementation of AES is vulnerable to a flush-and-reload… CVSS 3.1MEDIUM 5.9
TI-2017-06932 In Libgcrypt before 1.7.7, an attacker who learns the EdDSA session key (from… CVSS 3.0MEDIUM 5.9

See all 16 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences