CVE-2025-5853: A vulnerability classified as critical was found in Tenda AC6 15.03.05.16. Affected by this vulnerability is the function formSetSafeWanWebMan of the file…

PriorityP272high8.8CVSS 3.1

AVNACLPRLUINSUCHIHAH

EPSS

4.81%

90.9th percentile

A vulnerability classified as critical was found in Tenda AC6 15.03.05.16. Affected by this vulnerability is the function formSetSafeWanWebMan of the file /goform/SetRemoteWebCfg. The manipulation of the argument remoteIp leads to stack-based buffer overflow. The attack can be launched remotely. The exploit has been disclosed to the public and may be used.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
tenda	ac6	—	—
tenda	ac6_firmware	—	—

Detection & IOCsextracted from sources · hover to see the quote

path/goform/SetRemoteWebCfg↗

snort

alert http any any -> $HOME_NET any (msg:"ET WEB_SPECIFIC_APPS Tenda SetRemoteWebCfg remoteIp Parameter Buffer Overflow Attempt (CVE-2025-5853)"; flow:established,to_server; http.method; content:"POST"; http.uri; bsize:23; content:"/goform/SetRemoteWebCfg"; fast_pattern; http.request_body; content:"remoteIp"; pcre:"/^[^\x2c\x7d$]{100,}(?:\x2c|\x7d|$)/R"; reference:url,candle-throne-f75.notion.site/Tenda-AC15-formSetSafeWanWebMan-20adf0aa1185806daab3ebe0036266cb; reference:cve,2025-5853; classtype:web-application-attack; sid:2062821; rev:1; metadata:affected_product Tenda, attack_target Networking_Equipment, tls_state plaintext, created_at 2025_06_09, cve CVE_2025_5853, deployment Perimeter, deployment Internal, performance_impact Low, confidence High, signature_severity Major, tag Exploit, updated_at 2025_06_09, mitre_tactic_id TA0001, mitre_tactic_name Initial_Access, mitre_technique_id T1190, mitre_technique_name Exploit_Public_Facing_Application; target:dest_ip;)

→Exploit targets HTTP POST requests to the exact URI /goform/SetRemoteWebCfg (URI length is exactly 23 bytes); match on POST method and this URI path.
→The overflow is triggered via the 'remoteIp' parameter in the POST body; look for a remoteIp value exceeding 100 characters without a comma or closing brace delimiter.
→Attack is plaintext HTTP only (tls_state plaintext); TLS-encrypted traffic is not a concern for this exploit.
→Exploit is remotely launchable and publicly disclosed; prioritize perimeter and internal network monitoring for this signature.
→The vulnerable function is formSetSafeWanWebMan in the file /goform/SetRemoteWebCfg on Tenda AC6 firmware version 15.03.05.16; the manipulated argument is 'remoteIp' causing a stack-based buffer overflow. ↗

·Affected product is specifically Tenda AC6 firmware version 15.03.05.16; the Snort/ET rule references 'AC15' in the exploit write-up URL, suggesting the vulnerability or PoC may apply across multiple Tenda AC-series models. ↗
·The PCRE pattern /^[^\x2c\x7d$]{100,}(?:\x2c|\x7d|$)/R uses a relative offset anchor; ensure the IDS/IPS engine supports PCRE relative-offset matching (the /R flag) for accurate detection.

CVSS provenance

nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

nvdv4.07.4HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

nvdv2.09.0CRITICALAV:N/AC:L/Au:S/C:C/I:C/A:C

Stop checking back — get the weekly exploitation signal.

Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.