Cyber Resilience

CVE-2026-46727

Race Condition in Ruby-Lang Ruby 4.0.0 – 4.0.5

Race Condition
Published
22 May 2026
Modified
23 July 2026
Patch / advisory
View advisory
CVSS Score v3.1 8.1
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0048 39th percentile
Risk Priority 60 floored blend · peak EPSS

Summary

CVE-2026-46727 is a high-severity Race Condition (CWE-362) vulnerability in Ruby-Lang Ruby. Its CVSS base score is 8.1 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 39th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SC-39 (Process Isolation) and SC-4 (Information in Shared System Resources) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

A06:2025 Insecure Design

EU & UK References

Vulnerability Data

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…

more

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.

CWE(s)
CWE-362

Related Threats

MITRE ATT&CK Enterprise Techniques

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-27220Same product: Ruby-Lang Ruby
CVE-2024-53160Shared CWE-362
CVE-2024-54120Shared CWE-362
CVE-2023-52480Shared CWE-362
CVE-2023-31225Shared CWE-362
CVE-2025-38108Shared CWE-362
CVE-2026-23411Shared CWE-362
CVE-2025-38561Shared CWE-362
CVE-2024-47679Shared CWE-362
CVE-2023-42756Shared CWE-362

Affected Assets

ruby-lang
ruby
4.0.0 — 4.0.5

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V10.4.2
  • V10.4.5
  • V15.1.3
  • V15.4.1

Mitigating Controls (NIST 800-53 r5) AI

SC-39 Process Isolation partial match

Maintaining separate execution domains for each process structurally eliminates unintended concurrent access to the same shared resources.

SC-4 Information in Shared System Resources partial match

Preventing unintended information transfer through shared system resources directly addresses the improper concurrent modification that defines a race condition.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require proper synchronization primitives and concurrency testing that prevent race conditions.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing can detect race conditions, but does not prevent them at design or coding time.

A.8.25 Secure development life cycle partial match
prevents

Secure SDLC mandates concurrency controls and synchronization primitives that directly prevent race conditions.

A.8.26 Application security requirements partial match
prevents

Application security requirements can specify thread-safety and locking rules, but do not prescribe implementation details.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles require proper synchronization and resource isolation, addressing the root cause of CWE-362.

A.8.28 Secure coding partial match
prevents

Secure coding standards explicitly forbid unsafe concurrent access patterns and mandate atomic operations or locks.

A.8.32 Change management none match
none

Change management reduces introduction of concurrency bugs during updates, yet does not address the weakness itself.

References