How severe is CVE-2026-46727?

CVE-2026-46727 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-2026-46727 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-46727?

CVE-2026-46727 affects Ruby-lang Ruby. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-46727?

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.

Does CVE-2026-46727 have an EU (EUVD) identifier?

Yes. CVE-2026-46727 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31477.

When was CVE-2026-46727 published?

CVE-2026-46727 was published on 2026-05-22 and last updated on 2026-06-17.

CVE-2026-46727

CVE-2026-46727 is a high-severity vulnerability in Ruby-lang Ruby 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-362.

Key facts

Severity: High (CVSS 3.x base score 8.1)
EPSS exploit prediction: 0% (38th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-31477
Weakness: CWE-362
Affected product: Ruby-lang Ruby
Published: 2026-05-22
Last modified: 2026-06-17

Description

An issue was discovered in Ruby 4 before 4.0.5. A race condition leading to a use-after-free in the pthread-based getaddrinfo timeout handler (rb_getaddrinfo in ext/socket/raddrinfo.c) allows a remote attacker who can delay DNS responses near the user-specified timeout to crash a Ruby process that calls Addrinfo.getaddrinfo(..., timeout:) or Socket.tcp(..., resolv_timeout:). Memory-corruption-based exploitation is theoretically possible. The attack could, for example, be carried out through a crafted authoritative DNS server or recursive resolver.

Frequently asked questions

What is CVE-2026-46727?: An issue was discovered in Ruby 4 before 4.0.5. A race condition leading to a use-after-free in the pthread-based getaddrinfo timeout handler (rb_getaddrinfo in ext/socket/raddrinfo.c) allows a remote attacker who can delay DNS responses near the user-specified timeout to crash a Ruby process that calls Addrinfo.getaddrinfo(..., timeout:) or Socket.tcp(..., resolv_timeout:). Memory-corruption-based exploitation is theoretically possible. The attack could, for example, be carried out through a crafted authoritative DNS server or recursive resolver.
How severe is CVE-2026-46727?: CVE-2026-46727 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-2026-46727 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-46727?: CVE-2026-46727 affects Ruby-lang Ruby. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-46727?: 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.
Does CVE-2026-46727 have an EU (EUVD) identifier?: Yes. CVE-2026-46727 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-31477.
When was CVE-2026-46727 published?: CVE-2026-46727 was published on 2026-05-22 and last updated on 2026-06-17.

References

Affected products (1)

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

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