How severe is CVE-2018-6829?

CVE-2018-6829 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.

Is CVE-2018-6829 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-6829?

CVE-2018-6829 affects Gnupg Libgcrypt. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-6829?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2018-6829 published?

CVE-2018-6829 was published on 2018-02-07 and last updated on 2026-06-17.

CVE-2018-6829

CVE-2018-6829 is a high-severity vulnerability in Gnupg Libgcrypt with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-327.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (76th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-327
Affected product: Gnupg Libgcrypt
Published: 2018-02-07
Last modified: 2026-06-17

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.

Frequently asked questions

What is 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 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.
How severe is CVE-2018-6829?: CVE-2018-6829 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity none, and availability none.
Is CVE-2018-6829 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (76th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-6829?: CVE-2018-6829 affects Gnupg Libgcrypt. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-6829?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2018-6829 published?: CVE-2018-6829 was published on 2018-02-07 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:gnupg:libgcrypt:*:*:*:*:*:*:*:*

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