How severe is CVE-2009-4123?

CVE-2009-4123 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 high, integrity none, and availability none.

Is CVE-2009-4123 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-4123?

CVE-2009-4123 affects Jruby Jruby-openssl. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2009-4123?

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-2009-4123 published?

CVE-2009-4123 was published on 2023-12-12 and last updated on 2026-06-16.

CVE-2009-4123

CVE-2009-4123 is a high-severity vulnerability in Jruby Jruby-openssl 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-295.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (44th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-295
Affected product: Jruby Jruby-openssl
Published: 2023-12-12
Last modified: 2026-06-16

Description

The jruby-openssl gem before 0.6 for JRuby mishandles SSL certificate validation.

Frequently asked questions

What is CVE-2009-4123?: The jruby-openssl gem before 0.6 for JRuby mishandles SSL certificate validation.
How severe is CVE-2009-4123?: CVE-2009-4123 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 high, integrity none, and availability none.
Is CVE-2009-4123 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-4123?: CVE-2009-4123 affects Jruby Jruby-openssl. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2009-4123?: 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-2009-4123 published?: CVE-2009-4123 was published on 2023-12-12 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:jruby:jruby-openssl:*:*:*:*:*:*:*:*

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