How severe is CVE-2023-28756?

CVE-2023-28756 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2023-28756 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-28756?

CVE-2023-28756 primarily affects Ruby-lang Ruby. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-28756?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2023-28756 published?

CVE-2023-28756 was published on 2023-03-31 and last updated on 2026-06-17.

CVE-2023-28756

CVE-2023-28756 is a medium-severity vulnerability in Ruby-lang Ruby with a CVSS 3.x base score of 5.3. 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-1333.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 2% (82nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-1333
Affected product: Ruby-lang Ruby
Published: 2023-03-31
Last modified: 2026-06-17

Description

A ReDoS issue was discovered in the Time component through 0.2.1 in Ruby through 3.2.1. The Time parser mishandles invalid URLs that have specific characters. It causes an increase in execution time for parsing strings to Time objects. The fixed versions are 0.1.1 and 0.2.2.

Frequently asked questions

What is CVE-2023-28756?: A ReDoS issue was discovered in the Time component through 0.2.1 in Ruby through 3.2.1. The Time parser mishandles invalid URLs that have specific characters. It causes an increase in execution time for parsing strings to Time objects. The fixed versions are 0.1.1 and 0.2.2.
How severe is CVE-2023-28756?: CVE-2023-28756 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2023-28756 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (82nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-28756?: CVE-2023-28756 primarily affects Ruby-lang Ruby. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-28756?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-28756 published?: CVE-2023-28756 was published on 2023-03-31 and last updated on 2026-06-17.

References

Affected products (7)

cpe:2.3:a:ruby-lang:ruby:*:*:*:*:*:*:*:*
cpe:2.3:a:ruby-lang:time:0.1.0:*:*:*:*:ruby:*:*
cpe:2.3:a:ruby-lang:time:0.2.1:*:*:*:*:ruby:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:36:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:37:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:*

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