CVE-2023-27359Network attack vector

LAN service exposure via firewall-rule race

Published May 3, 2024 · Updated Sep 25, 2024

Firewall isolation bypass in TP-Link Archer AX21 firmware 3_1.1.1 allows remote attackers to reach LAN-only services without authentication. The hotplugd daemon handles firewall rules without proper synchronization, creating a race that temporarily exposes resources intended only for the LAN interface. Exploitation requires network access but no account; the flaw exposes internal services and enables root code execution only when chained with another vulnerability.

CVSS severity9.8
Critical
EPSS probability1.17%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Firewall isolation bypass in TP-Link Archer AX21 firmware 3_1.1.1 allows remote attackers to reach LAN-only services without authentication. The hotplugd daemon handles firewall rules without proper synchronization, creating a race that temporarily exposes resources intended only for the LAN interface. Exploitation requires network access but no account; the flaw exposes internal services and enables root code execution only when chained with another vulnerability.

The record

CVE
CVE-2023-27359
Published
May 3, 2024
Updated
Sep 25, 2024
Vendor
TP-Link
Product
Archer AX21 Firmware
Classifications
CWE-362, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 3, 2024CVE publishedPublication date reported by the CVE source.
  2. Sep 25, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=3_1.1.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

TP-Link · Archer AX21 Firmwareversion=3_1.1.1

Published CVSS scores

9.8Zero Day InitiativeCVSS:3.0/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
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-362Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
T1190Exploit Public-Facing Application

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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