CVE-2026-51843Public exploitNetwork attack vector

Remote code execution via unbounded wanMTU copy

Published Jun 19, 2026 · Updated Jun 19, 2026

Stack buffer overflow in the Tenda AC7 15.03.06.44 web interface allows remote attackers to execute code via a crafted wanMTU value. The check_param_changed function copies the user-controlled parameter into a stack buffer with strcpy without validating or limiting its length. The published proof of concept includes a password cookie, although CISA scores the attack as requiring no privileges; successful exploitation can crash the router or execute code.

CVSS severity9.8
Critical
EPSS probability0.56%
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 the Tenda AC7 15.03.06.44 web interface allows remote attackers to execute code via a crafted wanMTU value. The check_param_changed function copies the user-controlled parameter into a stack buffer with strcpy without validating or limiting its length. The published proof of concept includes a password cookie, although CISA scores the attack as requiring no privileges; successful exploitation can crash the router or execute code.

The record

CVE
CVE-2026-51843
Published
Jun 19, 2026
Updated
Jun 19, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-121
Attack vector
network
Privileges
Unavailable

Timeline

How it unfolded

  1. Jun 19, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 19, 2026Record 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 privilegesUnavailable in this record.

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
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-121Stack-based Buffer Overflow

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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