Cyber Posture

CVE-2026-1138

HighPublic PoC

Published: 19 January 2026

Published
19 January 2026
Modified
04 February 2026
KEV Added
Patch
CVSS Score 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0011 28.3th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-1138 is a high-severity Improper Restriction of Operations within the Bounds of a Memory Buffer (CWE-119) vulnerability in Utt 520W Firmware. Its CVSS base score is 8.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 28.3th 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 are NIST 800-53 SI-10 (Information Input Validation) and SI-16 (Memory Protection).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190) and 1 other technique. What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

Requires validation of inputs to the /goform/ConfigExceptQQ function to prevent buffer overflows from unchecked data in strcpy.

prevent

Mandates timely flaw remediation for vulnerabilities like this buffer overflow via patching, updates, or device replacement.

prevent

Enforces memory protections such as address space layout randomization and stack canaries to block exploitation of the buffer overflow.

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

Buffer overflow in router web interface (/goform/ConfigExceptQQ) enables remote exploitation of public-facing application (T1190) by authenticated low-privilege users, leading to arbitrary code execution and full system compromise consistent with exploitation for privilege escalation (T1068).

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

NVD Description

A flaw has been found in UTT 进取 520W 1.7.7-180627. This affects the function strcpy of the file /goform/ConfigExceptQQ. Executing a manipulation can lead to buffer overflow. The attack may be performed from remote. The exploit has been published and…

more

may be used. The vendor was contacted early about this disclosure but did not respond in any way.

Deeper analysisAI

CVE-2026-1138 is a buffer overflow vulnerability in the UTT 进取 520W router running firmware version 1.7.7-180627. The flaw resides in the strcpy function within the /goform/ConfigExceptQQ file, where improper handling of input leads to a buffer overflow condition. This issue corresponds to CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) and CWE-120 (Buffer Copy without Checking Size of Input), earning a CVSS v3.1 base score of 8.8 (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H), indicating high severity due to its potential for significant impact.

The vulnerability can be exploited remotely by an authenticated attacker with low privileges (PR:L), requiring no user interaction and low attack complexity over the network (AV:N/AC:L). Successful exploitation triggers a buffer overflow, potentially allowing arbitrary code execution with high impacts on confidentiality, integrity, and availability (C:H/I:H/A:H), such as full system compromise on the affected device.

Advisories from VulDB and a related GitHub repository detail the issue, noting that an exploit has been publicly disclosed and is available for use. The vendor was notified early but provided no response, and no patches or mitigations are mentioned in the available references. Security practitioners should isolate or decommission affected UTT 进取 520W devices where possible.

In notable context, the published exploit increases the risk of real-world attacks against unpatched instances of this router firmware.

Details

CWE(s)

Affected Products

utt
520w firmware
≤ 1.7.7-180627

CVEs Like This One

CVE-2026-1140Same product: Utt 520W
CVE-2026-2070Same product: Utt 520W
CVE-2026-2068Same product: Utt 520W
CVE-2026-0838Same product: Utt 520W
CVE-2026-1137Same product: Utt 520W
CVE-2025-15461Same product: Utt 520W
CVE-2026-0836Same product: Utt 520W
CVE-2026-0837Same product: Utt 520W
CVE-2025-15462Same product: Utt 520W
CVE-2026-0841Same product: Utt 520W

References