How severe is CVE-2018-3740?

CVE-2018-3740 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 none, integrity high, and availability none.

Is CVE-2018-3740 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-3740?

CVE-2018-3740 affects Sanitize Project Sanitize. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2018-3740?

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-2018-3740 published?

CVE-2018-3740 was published on 2018-03-30 and last updated on 2026-06-17.

CVE-2018-3740

CVE-2018-3740 is a high-severity vulnerability in Sanitize Project Sanitize 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-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 2% (72nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Sanitize Project Sanitize
Published: 2018-03-30
Last modified: 2026-06-17

Description

A specially crafted HTML fragment can cause Sanitize gem for Ruby to allow non-whitelisted attributes to be used on a whitelisted HTML element.

Frequently asked questions

What is CVE-2018-3740?: A specially crafted HTML fragment can cause Sanitize gem for Ruby to allow non-whitelisted attributes to be used on a whitelisted HTML element.
How severe is CVE-2018-3740?: CVE-2018-3740 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 none, integrity high, and availability none.
Is CVE-2018-3740 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-3740?: CVE-2018-3740 affects Sanitize Project Sanitize. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2018-3740?: 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-2018-3740 published?: CVE-2018-3740 was published on 2018-03-30 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:sanitize_project:sanitize:*:*:*:*:*:ruby:*:*

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