Cyber Resilience

CVE-2026-5071

Memory Safety in Zephyrproject Zephyr ≤ 4.3.0

Public PoCMemory Safety
Published
30 May 2026
Modified
22 July 2026
Patch / advisory
CVSS Score v3.1 6.1
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H
EPSS Score 0.0017 6th percentile
Risk Priority 35 floored blend · peak EPSS

Summary

CVE-2026-5071 is a medium-severity Out-of-bounds Read (CWE-125) vulnerability in Zephyrproject Zephyr. Its CVSS base score is 6.1 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Application or System Exploitation (T1499.004); ranked at the 6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

The strongest mitigations our analysis identified map to SI-10 (Information Input Validation) and SI-16 (Memory Protection) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

The SocketCAN implementation validates the length of a user-provided buffer containing a socketcan_frame object using only a NET_ASSERT statement in zcan_sendto_ctx() before dereferencing it in socketcan_to_can_frame(). In production builds where assertions are disabled, a userspace application that controls the length…

more

passed to a sendto syscall can supply an incomplete or truncated frame, causing socketcan_to_can_frame() to dereference fields beyond the end of the buffer. This results in an out-of-bounds read that can cause denial-of-service crashes or, because the parsed frame contents are transmitted on the network, leak adjacent memory.

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?

OOB read in kernel network stack from userspace syscall directly enables local system/application exploitation resulting in DoS crashes.

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

CVEs Like This One

CVE-2026-10657Same product: Zephyrproject Zephyr
CVE-2025-1673Same product: Zephyrproject Zephyr
CVE-2026-10658Same product: Zephyrproject Zephyr
CVE-2026-13351Same product: Zephyrproject Zephyr
CVE-2026-9263Same product: Zephyrproject Zephyr
CVE-2026-10652Same product: Zephyrproject Zephyr
CVE-2026-10593Same product: Zephyrproject Zephyr
CVE-2025-1675Same product: Zephyrproject Zephyr
CVE-2026-10637Same product: Zephyrproject Zephyr
CVE-2025-1674Same product: Zephyrproject Zephyr

Affected Assets

zephyrproject
zephyr
≤ 4.3.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • SI-10 Information Input Validation
  • SI-16 Memory Protection
Detect
Catch it (NIST detect / respond)
  • SI-4 System Monitoring
Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly requires validation of all input lengths and formats before processing, which would have rejected the truncated socketcan_frame supplied to sendto.

prevent

Implements memory bounds enforcement that can block or contain the out-of-bounds read performed by socketcan_to_can_frame on an undersized buffer.

detect

Requires continuous monitoring and anomaly detection that would flag the resulting crash or unexpected network frame contents caused by the OOB read.

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-development practices such as bounds checking and memory-safe languages directly prevent out-of-bounds reads.

ID.RA-01 partial match
prevents

Vulnerability scanning and recording can discover instances of out-of-bounds reads after code is deployed.

PR.PS-02 partial match
prevents

Routine patching replaces vulnerable code containing out-of-bounds read flaws.

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 and acceptance includes fuzzing and static analysis that detect out-of-bounds read defects before release.

A.8.15 Logging partial match
detects

Logging can record evidence of an out-of-bounds read but does not prevent the weakness itself.

prevents

Secure development life cycle mandates input validation and bounds checking that directly prevent out-of-bounds reads.

prevents

Application security requirements include explicit bounds and memory-safety specifications that mitigate buffer over-reads.

prevents

Secure system architecture and engineering principles require memory-safe design patterns and runtime protections against out-of-bounds access.

prevents

Secure coding standards explicitly forbid unsafe pointer arithmetic and mandate bounds-checked reads, eliminating CWE-125.

References