CVE-2026-1138
Published: 19 January 2026
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 7.4 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 46.4% of CVEs by exploit likelihood; 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).
Deeper analysis
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.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-3242
Vulnerability details
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…
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may be used. The vendor was contacted early about this disclosure but did not respond in any way.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
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).
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Requires validation of inputs to the /goform/ConfigExceptQQ function to prevent buffer overflows from unchecked data in strcpy.
Mandates timely flaw remediation for vulnerabilities like this buffer overflow via patching, updates, or device replacement.
Enforces memory protections such as address space layout randomization and stack canaries to block exploitation of the buffer overflow.