CVE-2025-55603Public exploitNetwork attack vector

Router crash via unchecked NTP server copy

Published Aug 22, 2025 · Updated Aug 22, 2025

Stack buffer overflow in Tenda AX3 firmware 16.03.12.10_CN allows remote attackers to crash the router via a crafted NTP server value. The SetSysTimeCfg handler copies the ntpServer parameter into a local stack variable without checking its length, overwriting the function return address. A network POST to /goform/SetSysTimeCfg demonstrates a persistent service crash; code execution is asserted by the researcher but not demonstrated.

CVSS severity7.5
High
EPSS probability0.41%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack buffer overflow in Tenda AX3 firmware 16.03.12.10_CN allows remote attackers to crash the router via a crafted NTP server value. The SetSysTimeCfg handler copies the ntpServer parameter into a local stack variable without checking its length, overwriting the function return address. A network POST to /goform/SetSysTimeCfg demonstrates a persistent service crash; code execution is asserted by the researcher but not demonstrated.

The record

CVE
CVE-2025-55603
Published
Aug 22, 2025
Updated
Aug 22, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-120, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 22, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 22, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

9.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
T1190Exploit Public-Facing Application

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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