CVE-2025-55847Public exploit

Code execution via unchecked Cookie length

Published Sep 26, 2025 · Updated Sep 26, 2025

Stack-based buffer overflow in Wavlink WL-WN586X3A firmware M86X3A_V240730 allows remote attackers to execute code via a Cookie header. The sub_400B90 function in ExportAllSettings.cgi fails to limit Cookie data before a controllable buffer write. An attacker must reach the router's web interface from an adjacent network; exploitation can corrupt memory, crash the device, or execute code.

CVSS severity8.8
High
EPSS probability2.04%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stack-based buffer overflow in Wavlink WL-WN586X3A firmware M86X3A_V240730 allows remote attackers to execute code via a Cookie header. The sub_400B90 function in ExportAllSettings.cgi fails to limit Cookie data before a controllable buffer write. An attacker must reach the router's web interface from an adjacent network; exploitation can corrupt memory, crash the device, or execute code.

The record

CVE
CVE-2025-55847
Published
Sep 26, 2025
Updated
Sep 26, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-120, T1499.004, T1210
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 26, 2025CVE publishedPublication date reported by the CVE source.
  2. Sep 26, 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 vectoradjacent
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.8CISA-ADPCVSS:3.1/AV:A/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.

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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)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
T1499.004Application or System Exploitation
T1210Exploitation of Remote Services

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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