Cyber Resilience

CVE-2025-7403

Zephyrproject Zephyr ≤ 4.1.0

Published
19 September 2025
Modified
29 October 2025
Patch / advisory
CVSS Score v3.1 7.6
Click a component to see what it means
Raw vectorCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H
EPSS Score 0.0019 9th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2025-7403 is a high-severity Write-what-where Condition (CWE-123) vulnerability in Zephyrproject Zephyr. Its CVSS base score is 7.6 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 9th 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 SI-16 (Memory Protection) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

Unsafe handling in bt_conn_tx_processor causes a use-after-free, resulting in a write-before-zero. The written 4 bytes are attacker-controlled, enabling precise memory corruption.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
Why these techniques?

Use-after-free memory corruption with attacker-controlled write enables local privilege escalation via exploitation.

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

CVEs Like This One

CVE-2026-0849Same product: Zephyrproject Zephyr
CVE-2026-10643Same product: Zephyrproject Zephyr
CVE-2026-1679Same product: Zephyrproject Zephyr
CVE-2026-10635Same product: Zephyrproject Zephyr
CVE-2026-10667Same product: Zephyrproject Zephyr
CVE-2026-10663Same product: Zephyrproject Zephyr
CVE-2026-5066Same product: Zephyrproject Zephyr
CVE-2026-8023Same product: Zephyrproject Zephyr
CVE-2023-6249Same product: Zephyrproject Zephyr
CVE-2026-10656Same product: Zephyrproject Zephyr

Affected Assets

zephyrproject
zephyr
≤ 4.1.0

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
Detect
Catch it (NIST detect / respond)
  • SI-7 Software, Firmware, and Information Integrity
Harden
Shrink the surface (DISA STIG)
  • 4 hardening rules · 4 OS baselines
Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly enforces memory protection mechanisms that block unauthorized writes, mitigating the attacker-controlled write-what-where primitive from the use-after-free.

prevent

Process isolation confines the effects of memory corruption in bt_conn_tx_processor, preventing the 4-byte write from affecting other security domains or kernel structures.

detect

Integrity verification of executing code and data can detect the precise memory corruption introduced by the flawed tx processor before further exploitation.

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 prevent arbitrary write conditions via safe coding, bounds checking, and memory-safe constructs.

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 can detect write-what-where conditions before deployment.

prevents

Secure development lifecycle practices directly reduce the likelihood of write-what-where flaws such as buffer overflows.

prevents

Application security requirements can mandate input validation and bounds checking that mitigate arbitrary write conditions.

prevents

Secure architecture and engineering principles discourage unsafe memory handling that leads to write-what-where vulnerabilities.

prevents

Secure coding standards explicitly forbid unsafe buffer operations that enable arbitrary memory writes.

prevents

Change management processes help ensure security fixes for such weaknesses are properly deployed.

References