How severe is CVE-2020-5529?

CVE-2020-5529 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-2020-5529 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-5529?

CVE-2020-5529 primarily affects Htmlunit. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2020-5529?

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-2020-5529 published?

CVE-2020-5529 was published on 2020-02-11 and last updated on 2026-06-17.

CVE-2020-5529

CVE-2020-5529 is a high-severity vulnerability in Htmlunit 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. The underlying weakness is classified as CWE-665.

Key facts

Severity: High (CVSS 3.x base score 8.1)
CVSS v2: 6.8
EPSS exploit prediction: 5% (91st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-665
Affected product: Htmlunit
Published: 2020-02-11
Last modified: 2026-06-17

Description

HtmlUnit prior to 2.37.0 contains code execution vulnerabilities. HtmlUnit initializes Rhino engine improperly, hence a malicious JavScript code can execute arbitrary Java code on the application. Moreover, when embedded in Android application, Android-specific initialization of Rhino engine is done in an improper way, hence a malicious JavaScript code can execute arbitrary Java code on the application.

Frequently asked questions

What is CVE-2020-5529?: HtmlUnit prior to 2.37.0 contains code execution vulnerabilities. HtmlUnit initializes Rhino engine improperly, hence a malicious JavScript code can execute arbitrary Java code on the application. Moreover, when embedded in Android application, Android-specific initialization of Rhino engine is done in an improper way, hence a malicious JavaScript code can execute arbitrary Java code on the application.
How severe is CVE-2020-5529?: CVE-2020-5529 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-2020-5529 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 5% (91st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-5529?: CVE-2020-5529 primarily affects Htmlunit. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2020-5529?: 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-2020-5529 published?: CVE-2020-5529 was published on 2020-02-11 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:htmlunit:htmlunit:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:*
cpe:2.3:a:apache:camel:-:*:*:*:*:*:*:*

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CVE-2015-8367 — Critical (CVSS 9.8): The phase_one_correct function in Libraw before 0.17.1 allows attackers to cause memory errors and possibly execute…
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