How severe is CVE-2022-28738?

CVE-2022-28738 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2022-28738 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-28738?

CVE-2022-28738 affects Ruby-lang Ruby. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2022-28738?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2022-28738 published?

CVE-2022-28738 was published on 2022-05-09 and last updated on 2026-06-17.

CVE-2022-28738

CVE-2022-28738 is a critical-severity vulnerability in Ruby-lang Ruby with a CVSS 3.x base score of 9.8. 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-415.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v2: 7.5
EPSS exploit prediction: 3% (84th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-415
Affected product: Ruby-lang Ruby
Published: 2022-05-09
Last modified: 2026-06-17

Description

A double free was found in the Regexp compiler in Ruby 3.x before 3.0.4 and 3.1.x before 3.1.2. If a victim attempts to create a Regexp from untrusted user input, an attacker may be able to write to unexpected memory locations.

Frequently asked questions

What is CVE-2022-28738?: A double free was found in the Regexp compiler in Ruby 3.x before 3.0.4 and 3.1.x before 3.1.2. If a victim attempts to create a Regexp from untrusted user input, an attacker may be able to write to unexpected memory locations.
How severe is CVE-2022-28738?: CVE-2022-28738 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2022-28738 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (84th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-28738?: CVE-2022-28738 affects Ruby-lang Ruby. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2022-28738?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2022-28738 published?: CVE-2022-28738 was published on 2022-05-09 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:ruby-lang:ruby:*:*:*:*:*:*:*:*

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