Security Resilience

CVE-2023-26976

Memory Safety in Tenda Ac6 Firmware 15.03.05.09

Public PoCMemory Safety
Published
04 April 2023
Modified
13 February 2025
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 0.16 97th percentile
Risk Priority 79 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2023-26976 is a high-severity Out-of-bounds Write (CWE-787) vulnerability in Tenda Ac6 Firmware. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Security Account Manager (T1003.002); ranked in the top 3% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

Tenda AC6 firmware version 15.03.05.09_multi contains a stack-based buffer overflow in the form_fast_setting_wifi_set function triggered by the ssid parameter. The flaw is tracked as CVE-2023-26976 and carries a CVSS 3.1 score of 7.5, reflecting network-reachable unauthenticated input that results in an out-of-bounds write (CWE-787) and high availability impact.

An unauthenticated attacker can supply an oversized or malformed ssid value in a single HTTP request to the affected endpoint, causing the device to crash or become unresponsive. Because the call requires no credentials and can be issued remotely, the vulnerability allows denial-of-service against any exposed administrative interface.

Public references consist of GitHub repositories documenting the issue but contain no vendor advisory, firmware update, or mitigation guidance. The associated EPSS score rose from a low baseline to a peak of 0.5558 before receding to its current value of 0.1862, indicating a period of elevated exploitation interest after disclosure.

EU & UK References

Vulnerability Data

Tenda AC6 v15.03.05.09_multi was discovered to contain a stack overflow via the ssid parameter in the form_fast_setting_wifi_set function.

CWE(s)
CWE-787

Related Threats

MITRE ATT&CK Enterprise Techniques

T1003.002 Security Account Manager Credential Access
Adversaries may attempt to extract credential material from the Security Account Manager (SAM) database either through in-memory techniques or through the Windows Registry where the SAM database is stored.
attack.mitre.org →
T1003.004 LSA Secrets Credential Access
Adversaries with SYSTEM access to a host may attempt to access Local Security Authority (LSA) secrets, which can contain a variety of different credential materials, such as credentials for service accounts.
attack.mitre.org →
T1003.008 /etc/passwd and /etc/shadow Credential Access
Adversaries may attempt to dump the contents of <code>/etc/passwd</code> and <code>/etc/shadow</code> to enable offline password cracking.
attack.mitre.org →
T1006 Direct Volume Access Stealth
Adversaries may directly access a volume to bypass file access controls and file system monitoring.
attack.mitre.org →
T1007 System Service Discovery Discovery
Adversaries may try to gather information about registered local system services.
attack.mitre.org →
T1012 Query Registry Discovery
Adversaries may interact with the Windows Registry to gather information about the system, configuration, and installed software.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-29031Same product: Tenda Ac6
CVE-2023-40848Same product: Tenda Ac6
CVE-2023-40841Same product: Tenda Ac6
CVE-2023-40846Same product: Tenda Ac6
CVE-2023-40840Same product: Tenda Ac6
CVE-2023-40845Same product: Tenda Ac6
CVE-2023-40842Same product: Tenda Ac6
CVE-2023-40847Same product: Tenda Ac6
CVE-2025-29029Same product: Tenda Ac6
CVE-2023-40843Same product: Tenda Ac6

Affected Assets

tenda
ac6 firmware
15.03.05.09

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

SI-16 Memory Protection
addresses: CWE-787

Out-of-bounds writes that corrupt control flow or inject shellcode are rendered non-executable by the same memory protections.

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.

ID.RA-01 partial match
blocks

Vulnerability scanning and recording can discover out-of-bounds write flaws so they can be remediated.

PR.PS-02 partial match
blocks

Patching or replacing vulnerable software directly eliminates known instances of this coding weakness.

PR.PS-06 partial match
blocks

Secure-development practices (static analysis, bounds checking, code review) are the primary means of preventing out-of-bounds writes.

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.

A.5.14 Information transfer partial match
removes
A.5.15 Access control partial match
removes
A.5.16 Identity management partial match
removes
A.5.17 Authentication information partial match
removes
A.5.18 Access rights partial match
removes
A.7.2 Physical entry partial match
removes

References