CVE-2018-8970

The int_x509_param_set_hosts function in lib/libcrypto/x509/x509_vpm.c in LibreSSL 2.7.0 before 2...

7.4 HighPublic exploitFix available

The int_x509_param_set_hosts function in lib/libcrypto/x509/x509_vpm.c in LibreSSL 2.7.0 before 2.7.1 does not support a certain special case of a zero name length, which causes silent omission of hostname verification, and consequently allows man-in-the-middle attackers to spoof servers and obtain sensitive information via a crafted certificate. NOTE: the LibreSSL documentation indicates that this special case is supported, but the BoringSSL documentation does not.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: High
Privileges needed: None
User interaction: None

What an attacker can affect

Confidentiality: High
Integrity: High
Availability: None

Exploit likelihood

1.02%Down 2.6 points since Apr 14, 2021

What each source reports

NVD Score used 7.4

Record: CVE-2018-8970
CVSS 3.0: 7.4 HighCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
CVSS 2.0: 5.8 MediumAV:N/AC:M/Au:N/C:P/I:P/A:N
Weakness: CWE-295
Updated: 2026-11-02

CVE List No score

Record: CVE-2018-8970
Updated: 2026-11-02

EUVDEUVD-2018-20577 No score

Record: EUVD-2018-20577
Updated: 2026-11-03

GitHub AdvisoriesGHSA-7gr4-mrjx-cjx9 7.4

The int_x509_param_set_hosts function in lib/libcrypto/x509/x509_vpm.c in LibreSSL 2.7.0 before 2...

Record: GHSA-7gr4-mrjx-cjx9
CVSS 3.0: 7.4 HighCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Weakness: CWE-295
Updated: 2026-11-02

OSV 7.4

Record: CVE-2018-8970
CVSS 3.0: 7.4 HighCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N
Updated: 2026-11-02

OSVopenSUSE-SU-2024:10985-1 No score

libcrypto46-3.3.4-1.2 on GA media

These are all security issues fixed in the libcrypto46-3.3.4-1.2 package on the GA media of openSUSE Tumbleweed.

Record: openSUSE-SU-2024:10985-1
Updated: 2026-11-02

Affected products

openbsd libressl

Affected packages

Affected packages
Package	Affected	Fixed
`libressl` openSUSE:Tumbleweed	before 3.3.4-1.2	3.3.4-1.2

Public exploits

Links only. Every CVE stores no exploit code.

Public exploits
Source	Link	Date
PoC in GitHub	tiran/CVE-2018-8970	2018-03-25

History

History
Recorded	Changed	Sources
Nov 3, 2026	aliases	EUVD
Nov 2, 2026	first indexed	CVE List, GitHub Advisories, NVD, OSV, PoC in GitHub

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2018-8970 is a high vulnerability (CVSS 7.4) in Openbsd Libressl, published March 24, 2018. Public exploit code exists. EPSS puts the chance of exploitation in the next 30 days at 1.02%, the 63rd percentile. Fixed in libressl 3.3.4-1.2.