CVE-2026-129258

Tenda AC18 Firmware Upgrade upgrade data authenticity

publishedCWE-345

A vulnerability was identified in Tenda AC18 15.03.05.05_multi/15.03.05.19 Build 6318. Affected by this vulnerability is an unknown functionality of the file /cgi-bin/upgrade of the component Firmware Upgrade Handler. Such manipulation of the argument upgradeFile leads to insufficient verification of data authenticity. The attack may be launched remotely. The exploit is publicly available and might be used.

Technical severity9.4 criticalCVSS 4.0 · CNA: VulDB

Published2026-11-14Source updated 2026-11-14

Collected2026-11-141 attributed source

Fixes and workarounds

Fix

The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.

Source: CNA: VulDB

Affected products and versions

Affected products, source version ranges and reporting authorities
Product	Versions	Authority
AC18 Tenda	15.03.05.05_multi (affected) 15.03.05.19 Build 6318 (affected)	CNA: VulDB

Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.

CVSS assessments

CVSS scores, vectors and reporting authorities
Version / score	Vector	Authority
4.0 / 9.4 critical	`CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:P`	CNA: VulDB
3.1 / 9.1 critical	`CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H/E:P/RL:X/RC:C`	CNA: VulDB
3.0 / 9.1 critical	`CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H/E:P/RL:X/RC:C`	CNA: VulDB
2.0 / 8.3 high	`AV:N/AC:L/Au:M/C:C/I:C/A:C/E:POC/RL:ND/RC:C`	CNA: VulDB

Exploit evidence

https://github.com/longqx223/Tenda-ac-18-V15.03.05.05-/blob/main/2026-10-19-Tenda-AC18-unsigned-firmware-update-advisory-EN.pdf
exploit · CNA: VulDB

References

https://vuldb.com/vuln/437295CNA: VulDB · vdb-entry, technical-description
https://vuldb.com/vuln/437295/ctiCNA: VulDB · signature, permissions-required
https://vuldb.com/cve/CVE-2026-129258CNA: VulDB · third-party-advisory
https://vuldb.com/submit/1043033CNA: VulDB · third-party-advisory
https://github.com/longqx223/Tenda-ac-18-V15.03.05.05-/blob/main/2026-10-19-Tenda-AC18-unsigned-firmware-update-advisory-EN.pdfCNA: VulDB · exploit, patch
https://www.tenda.com.cn/CNA: VulDB · product

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