Cyber Resilience

CVE-2026-51266

Memory Safety

Published
28 July 2026
Modified
28 July 2026
CVSS Score v3.1 9.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0063 47th percentile
Risk Priority 70 floored blend · peak EPSS

Summary

CVE-2026-51266 is a critical-severity Heap-based Buffer Overflow (CWE-122) vulnerability. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 47th 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 SI-2 (Flaw Remediation) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

schreibfaul1 ESP32-audioI2S 3.4.5 has a heap-based buffer overflow vulnerability in the HTTP request header construction logic. The application dynamically splices attacker-controlled host name, path, query string, and multiple HTTP header fields into a fixed ps_ptr heap buffer without proper size…

more

limitation and boundary validation. Remote attackers can use an oversized crafted network request parameter to trigger out-of-bounds heap write, leading to arbitrary code execution.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Why these techniques?

Heap buffer overflow in HTTP request construction allows remote attackers to supply oversized parameters leading directly to arbitrary code execution on a network-accessible device/application.

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

CVEs Like This One

CVE-2026-26967Shared CWE-122
CVE-2025-67896Shared CWE-122
CVE-2026-45542Shared CWE-122
CVE-2025-34523Shared CWE-122
CVE-2026-46752Shared CWE-122
CVE-2026-34865Shared CWE-122
CVE-2026-22891Shared CWE-122
CVE-2026-55010Shared CWE-122
CVE-2019-25327Shared CWE-122
CVE-2025-60724Shared CWE-122

Affected Assets

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-2 Flaw Remediation
Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V1.4.1

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly enforces validation of all untrusted HTTP header fields (host, path, query) before they are spliced into the fixed ps_ptr buffer, blocking the oversized inputs that trigger the heap overflow.

prevent

Applies memory protection mechanisms that can detect or block out-of-bounds heap writes during HTTP request construction, limiting exploitability of the CWE-122 flaw.

respondrecover

Requires timely patching or replacement of the vulnerable ESP32-audioI2S 3.4.5 library once the buffer-handling defect is identified.

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 full match
prevents

Secure-development practices directly require bounds checking and safe memory handling that prevent heap overflows.

ID.RA-01 partial match
prevents

Vulnerability scanning and recording can discover heap-overflow flaws but does not prevent their introduction in code.

PR.PS-02 partial match
prevents

Timely patching removes known heap-overflow instances after they exist.

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 heap overflows before release.

prevents

Secure development lifecycle mandates practices that reduce the likelihood of introducing heap overflows.

prevents

Application security requirements can specify bounds-checking and safe memory APIs that mitigate heap overflows.

prevents

Secure architecture and engineering principles include memory-safety and input-validation controls that address heap overflows.

prevents

Secure coding standards directly prescribe techniques (safe functions, bounds checks) that prevent heap-based buffer overflows.

none

Change management ensures controlled deployment of fixes for discovered heap-overflow vulnerabilities.

References