CVE-2026-36613

Adjacent memory disclosure via undefined-path POST handling

Published Jun 3, 2026 · Updated Jun 3, 2026

Information disclosure in Mercusys AC12G (EU) V1 firmware AC12G(EU)_V1_200909 allows remote attackers to read memory via crafted POST requests. The VxWorks POST handler sends its 128-byte header-parsing buffer for undefined paths and reads 67 bytes beyond an included body into adjacent heap memory. No authentication is required, but the attacker must be on the device's LAN; responses expose headers, prior response fragments, and stable memory addresses.

CVSS severity4.3
Medium
EPSS probability0.16%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in Mercusys AC12G (EU) V1 firmware AC12G(EU)_V1_200909 allows remote attackers to read memory via crafted POST requests. The VxWorks POST handler sends its 128-byte header-parsing buffer for undefined paths and reads 67 bytes beyond an included body into adjacent heap memory. No authentication is required, but the attacker must be on the device's LAN; responses expose headers, prior response fragments, and stable memory addresses.

The record

CVE
CVE-2026-36613
Published
Jun 3, 2026
Updated
Jun 3, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-125
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 3, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 3, 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 vectoradjacent
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

4.3CISA-ADPCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-125Out-of-bounds Read

Public exploit references

No public exploit references are available in this record.

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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