Cyber Posture

CVE-2026-2886

HighPublic PoC

Published: 21 February 2026

Published
21 February 2026
Modified
23 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 29.3th percentile
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Description

A weakness has been identified in Tenda A21 1.0.0.0. This affects the function set_device_name of the file /goform/SetOnlineDevName. This manipulation of the argument devName causes stack-based buffer overflow. It is possible to initiate the attack remotely. The exploit has been…

more

made available to the public and could be used for attacks.

Mitigating Controls (NIST 800-53 r5)AI

prevent

Remediating the stack-based buffer overflow flaw in the set_device_name function via firmware updates directly prevents exploitation of CVE-2026-2886.

prevent

Validating the devName argument at the /goform/SetOnlineDevName endpoint ensures inputs do not exceed buffer bounds, directly addressing the improper restriction of operations causing the overflow.

prevent

Memory protections such as stack canaries, ASLR, and DEP safeguard against successful exploitation of the stack-based buffer overflow even if invalid inputs are processed.

Security SummaryAI

CVE-2026-2886 is a stack-based buffer overflow vulnerability in Tenda A21 firmware version 1.0.0.0. The issue affects the set_device_name function in the /goform/SetOnlineDevName endpoint, where improper handling of the devName argument allows overflow. Published on 2026-02-21, it is rated 8.8 on the CVSS 3.1 scale (AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H) and maps to CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) and CWE-121 (Stack-based Buffer Overflow).

The vulnerability is remotely exploitable over the network with low attack complexity and requires low privileges, such as those of an authenticated user. Successful exploitation can result in high-impact confidentiality, integrity, and availability violations, potentially enabling remote code execution on the affected device.

Advisories referenced in VULDB entries (ctiid.347180, id.347180, submit.754640) and a GitHub issue (QIU-DIE/cve-nneeww/issues/6) detail the vulnerability and confirm a public exploit is available, increasing the risk of attacks. The Tenda vendor website (tenda.com.cn) is listed as a reference, where security practitioners should check for any firmware updates or mitigation guidance.

Details

CWE(s)

Affected Products

tenda
a21 firmware
1.0.0.0

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?

Stack-based buffer overflow in web management endpoint (/goform/SetOnlineDevName) allows remote code execution with low privileges (authenticated user), directly enabling exploitation of a public-facing application.

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

References