How severe is CVE-2018-16396?

CVE-2018-16396 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2018-16396 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 8% (94th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-16396?

CVE-2018-16396 primarily affects Ruby-lang Ruby. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-16396?

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-2018-16396 published?

CVE-2018-16396 was published on 2018-11-16 and last updated on 2026-06-17.

CVE-2018-16396

CVE-2018-16396 is a high-severity vulnerability in Ruby-lang Ruby with a CVSS 3.x base score of 8.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v2: 6.8
EPSS exploit prediction: 8% (94th percentile)
Actively exploited: Not listed in CISA KEV
Affected product: Ruby-lang Ruby
Published: 2018-11-16
Last modified: 2026-06-17

Description

An issue was discovered in Ruby before 2.3.8, 2.4.x before 2.4.5, 2.5.x before 2.5.2, and 2.6.x before 2.6.0-preview3. It does not taint strings that result from unpacking tainted strings with some formats.

Frequently asked questions

What is CVE-2018-16396?: An issue was discovered in Ruby before 2.3.8, 2.4.x before 2.4.5, 2.5.x before 2.5.2, and 2.6.x before 2.6.0-preview3. It does not taint strings that result from unpacking tainted strings with some formats.
How severe is CVE-2018-16396?: CVE-2018-16396 has a CVSS 3.x base score of 8.1, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2018-16396 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 8% (94th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-16396?: CVE-2018-16396 primarily affects Ruby-lang Ruby. In total, 14 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-16396?: 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-2018-16396 published?: CVE-2018-16396 was published on 2018-11-16 and last updated on 2026-06-17.

References

Affected products (14)

cpe:2.3:a:ruby-lang:ruby:*:*:*:*:*:*:*:*
cpe:2.3:a:ruby-lang:ruby:2.6.0:preview1:*:*:*:*:*:*
cpe:2.3:a:ruby-lang:ruby:2.6.0:preview2:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:18.10:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:7.0:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:7.4:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:7.5:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux:7.6:*:*:*:*:*:*:*

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