Cyber Resilience

CVE-2026-58250

Memory Safety in Linuxfoundation Nats-Server ≤ 2.11.17

Published
08 July 2026
Modified
13 July 2026
Patch / advisory
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0050 40th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2026-58250 is a high-severity NULL Pointer Dereference (CWE-476) vulnerability in Linuxfoundation Nats-Server. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Application or System Exploitation (T1499.004); ranked at the 40th 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 AC-3 (Access Enforcement) and SC-7 (Boundary Protection) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.12.8 and 2.11.17, an unauthenticated peer with network access to a leafnode listener with compression enabled could crash the server during the pre-authentication…

more

leafnode handshake by sending repeated leafnode INFO protocol messages before authentication and account setup completed. This issue is fixed in versions 2.12.8 and 2.11.17.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1499.004 Application or System Exploitation Impact
Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.
Why these techniques?

The unauthenticated remote attacker can crash the NATS Server by sending crafted leafnode INFO messages over the network, directly mapping to Application or System Exploitation (T1499.004) for denial of service.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2026-29785Same product: Linuxfoundation Nats-Server
CVE-2026-33219Same product: Linuxfoundation Nats-Server
CVE-2026-58207Same product: Linuxfoundation Nats-Server
CVE-2026-58208Same product: Linuxfoundation Nats-Server
CVE-2026-33218Same product: Linuxfoundation Nats-Server
CVE-2026-27571Same product: Linuxfoundation Nats-Server
CVE-2026-27889Same product: Linuxfoundation Nats-Server
CVE-2026-33216Same product: Linuxfoundation Nats-Server
CVE-2026-33223Same product: Linuxfoundation Nats-Server
CVE-2026-58209Same product: Linuxfoundation Nats-Server

Affected Assets

linuxfoundation
nats-server
≤ 2.11.17 · 2.12.0 — 2.12.8

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • SC-7 Boundary Protection
  • AC-3 Access Enforcement
  • SI-10 Information Input Validation
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

prevent

Boundary protection restricts which external systems can reach the leafnode listener, directly blocking the unauthenticated network peer that triggers the crash.

prevent

Access enforcement ensures the leafnode handshake cannot proceed until authentication and account setup are complete, eliminating the pre-auth window exploited by the repeated INFO messages.

prevent

Input validation on the leafnode protocol stream can reject or rate-limit repeated INFO messages before they reach the vulnerable code path that dereferences a null pointer.

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 (static analysis, code review, safe coding standards) directly prevent NULL dereference bugs during development.

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.

detects

Security testing can detect NULL dereference defects before release.

prevents

Secure SDLC mandates defensive coding practices that can prevent NULL dereferences.

prevents

Application security requirements can specify input validation and pointer-safety rules.

prevents

Secure architecture principles encourage defensive design that avoids unsafe pointer use.

prevents

Secure coding standards directly require NULL-pointer checks and safe dereference patterns.

References