7.4

CVE-2018-8970: openbsd libressl Improper Certificate Validation

CVSS: 7.4v3.0HighModified
Published 24-03-2018Last modified 05-08-2024
Open JSON

Vulnerability summary

CVE-2018-8970 is a high (CVSS 7.4) Improper Certificate Validation vulnerability in openbsd libressl. EPSS estimates a 1.02% chance of exploitation in the next 30 days, higher than 62.7% of scored vulnerabilities.

Overall risk
30/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.4/10
010
High · v3.0 (NVD)
EPSS score
1.02%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 1 · Related 1
OPENSUSE-SU-2024:10985-1

Timeline

  1. 24-03-2018
    PublishedVulnerability first disclosed.
  2. 05-08-2024
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

2 scores · 1 source · 2 versions

EPSS trend

Probability

1.02%

Chance of exploitation in the next 30 days

Percentile

63%

Versus all other CVEs

30-day change

0.00 pp

From 1.02% on 18-09-2026

18-09-202618-10-2026
EPSS score
1.02%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Openbsd1 product

1 vendor · 1 product

References

3 links