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.

Published: 2026-05-22 Last update: 2026-05-26 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-46727 is rated Moderate Risk (45.3/100): CVSS High severity, with low exploitation likelihood (EPSS 0.16%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-46727

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-28 0.10% 0.16% +0.06%
2 2026-05-23 — 0.10% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-46727

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.1 3.1 HIGH
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.2 5.9 [email protected]

Weakness enumeration for CVE-2026-46727

GitHub Security Advisory for CVE-2026-46727

GHSA-jfc8-2xw7-c79m · Severity: high — An issue was discovered in Ruby 4 before 4.0.5. A race condition leading to a use-after-free in...

OS Trackers for CVE-2026-46727

vendor priority summary link
suse high CVE-2026-46727 severity important: SUSE including 11 source package names (libruby2_1-2_1, libruby2_5-2_5, …), 105 product×package rows across 20 product lines (SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS, SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS, … (20 product lines)): Known Not Affected 105. https://www.suse.com/security/cve/CVE-2026-46727/
ubuntu medium CVE-2026-46727 medium priority: Ubuntu including 7 source packages (jruby, ruby2.3, …), 41 status rows across 9 suites (bionic, focal, jammy, noble, questing, resolute, trusty, upstream, xenial): DNE 21, needs-triage 20. https://ubuntu.com/security/CVE-2026-46727

Affected software / configurations for CVE-2026-46727

Vendor Product Version Raw CPE
ruby-lang ruby >= 4.0.0, < 4.0.5 cpe:2.3:a:ruby-lang:ruby:*:*:*:*:*:*:*:*

References for CVE-2026-46727

cvelogic Threat Intelligence