Cyber Resilience

CVE-2026-58207

Memory Safety in Linuxfoundation Nats-Server 2.12.0 – 2.12.12

Published
08 July 2026
Modified
09 July 2026
Patch / advisory
CVSS Score v3.1 7.7
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
EPSS Score 0.0040 32th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2026-58207 is a high-severity Integer Overflow or Wraparound (CWE-190) vulnerability in Linuxfoundation Nats-Server. Its CVSS base score is 7.7 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Application or System Exploitation (T1499.004); ranked at the 32th 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 SI-10 (Information Input Validation) and SC-7 (Boundary Protection) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

NATS Server is a high-performance server for NATS.io, the cloud and edge native messaging system. Prior to 2.14.3 and 2.12.12, a client able to send account-scoped connection monitoring requests could crash the server by supplying Connz pagination Offset and Limit…

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values that overflowed internal arithmetic before the response window was safely bounded. This issue is fixed in versions 2.14.3 and 2.12.12.

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?

Integer overflow (CWE-190) in Connz pagination handling allows a remote authenticated client to crash the NATS server, directly mapping to application exhaustion via crafted requests.

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

CVEs Like This One

CVE-2026-33219Same product: Linuxfoundation Nats-Server
CVE-2026-58208Same product: Linuxfoundation Nats-Server
CVE-2026-58250Same product: Linuxfoundation Nats-Server
CVE-2026-33218Same product: Linuxfoundation Nats-Server
CVE-2026-27889Same product: Linuxfoundation Nats-Server
CVE-2026-29785Same product: Linuxfoundation Nats-Server
CVE-2026-27571Same 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
2.12.0 — 2.12.12 · 2.14.0 — 2.14.3

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • SI-10 Information Input Validation
  • SC-7 Boundary Protection
  • SI-2 Flaw Remediation
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V5.2.6

Mitigating Controls (NIST 800-53 r5) AI

prevent

Input validation of the Offset and Limit parameters in Connz monitoring requests would reject or safely bound the values before arithmetic overflow occurs.

prevent

Boundary protection can restrict which clients are permitted to issue account-scoped connection monitoring requests, reducing the attack surface.

prevent

Timely application of the vendor-supplied patches (2.14.3 / 2.12.12) eliminates the integer-overflow flaw in the Connz handler.

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 use of safe arithmetic, bounds checks, and testing that prevent integer overflows.

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 in development can detect integer overflows before release.

prevents

Secure SDLC mandates input validation and arithmetic checks that prevent integer overflows.

degrades

Application security requirements include bounds checking and safe arithmetic to avoid overflow conditions.

degrades

Secure architecture principles require defensive coding patterns that mitigate integer wraparound risks.

prevents

Secure coding standards explicitly forbid unsafe integer operations and mandate overflow-safe constructs.

References