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 (rbgetaddrinfo 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(..., resolvtimeout:). Memory-corruption-based exploitation is theoretically possible. The attack could, for example, be carried out through a crafted authoritative DNS server or recursive resolver.

Database specific

{
    "unresolved_ranges": [
        {
            "source": "AFFECTED_FIELD",
            "extracted_events": [
                {
                    "introduced": "4.0.0"
                },
                {
                    "fixed": "4.0.5"
                }
            ]
        },
        {
            "source": "CPE_FIELD",
            "extracted_events": [
                {
                    "introduced": "4.0.0"
                },
                {
                    "fixed": "4.0.5"
                }
            ]
        },
        {
            "source": "DESCRIPTION",
            "extracted_events": [
                {
                    "introduced": "4"
                },
                {
                    "fixed": "4.0.5"
                }
            ]
        }
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/46xxx/CVE-2026-46727.json",
    "cna_assigner": "mitre",
    "cwe_ids": [
        "CWE-362"
    ]
}

References

Affected packages

Git / github.com/ruby/ruby

Affected ranges

Type

GIT

Repo

https://github.com/ruby/ruby

Events

Introduced

553f1675f3a9cece340b90f374a4245dccac2272

Fixed

64336ffd0ee9e1f4c05891695a3d7b49cb709721

Database specific

{
    "source": "CPE_RANGE",
    "cpe": "cpe:2.3:a:ruby-lang:ruby:*:*:*:*:*:*:*:*",
    "extracted_events": [
        {
            "introduced": "4.0.0"
        },
        {
            "fixed": "4.0.5"
        }
    ]
}

Affected versions

v4.*

v4.0.0

v4.0.1

v4.0.2

v4.0.3

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-46727.json"