CVE-2026-12339: CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') in TP-Link Systems Inc. TL-MR6400 v5.3
A Zip Slip vulnerability in the WebUI ISP Upgrade functionality allows arbitrary file write via a crafted archive containing directory traversal sequences. An authenticated administrator may overwrite arbitrary files on the system.Successful exploitation may allow arbitrary file to be overwritten on the underlying system, affecting system integrity and availability.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-12339) is a CWE-22 path traversal issue in the TL-MR6400 v5.3 router's WebUI ISP Upgrade functionality. An authenticated administrator can exploit a Zip Slip vulnerability by providing a specially crafted archive with directory traversal sequences, enabling arbitrary file overwrite on the underlying system. This compromises the system's integrity and availability. The CVSS 4.0 base score is 6.9, indicating medium severity. No patch or official remediation has been disclosed by the vendor as of the publication date.
Potential Impact
Successful exploitation allows an authenticated administrator to overwrite arbitrary files on the device filesystem. This can lead to system integrity compromise and potentially disrupt system availability. The vulnerability requires administrator privileges and network access to the device's WebUI.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict administrator access to the WebUI and validate uploaded archives carefully to mitigate exploitation risk.
CVE-2026-12339: CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') in TP-Link Systems Inc. TL-MR6400 v5.3
Description
A Zip Slip vulnerability in the WebUI ISP Upgrade functionality allows arbitrary file write via a crafted archive containing directory traversal sequences. An authenticated administrator may overwrite arbitrary files on the system.Successful exploitation may allow arbitrary file to be overwritten on the underlying system, affecting system integrity and availability.
CVSS v4.0
Score 6.9medium
Affected software
TP-Link Systems Inc.
TL-MR6400 v5.3
TP-Link Systems Inc.
Archer MR600 v2
TP-Link Systems Inc.
Archer MR200 v7
TP-Link Systems Inc.
TL-MR6400 v8.0
TP-Link Systems Inc.
TL-MR150 v3.20
TP-Link Systems Inc.
TL-MR100 v3.20
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-12339) is a CWE-22 path traversal issue in the TL-MR6400 v5.3 router's WebUI ISP Upgrade functionality. An authenticated administrator can exploit a Zip Slip vulnerability by providing a specially crafted archive with directory traversal sequences, enabling arbitrary file overwrite on the underlying system. This compromises the system's integrity and availability. The CVSS 4.0 base score is 6.9, indicating medium severity. No patch or official remediation has been disclosed by the vendor as of the publication date.
Potential Impact
Successful exploitation allows an authenticated administrator to overwrite arbitrary files on the device filesystem. This can lead to system integrity compromise and potentially disrupt system availability. The vulnerability requires administrator privileges and network access to the device's WebUI.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict administrator access to the WebUI and validate uploaded archives carefully to mitigate exploitation risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- TPLink
- Date Reserved
- 2026-06-15T15:51:52.827Z
- Cvss Version
- 4.0
- State
- PUBLISHED
Threat ID: 6a7a1b7bbf8831d5395475e1
Added to database: 08/10/2026, 18:42:03 UTC
Last enriched: 08/10/2026, 18:59:49 UTC
Last updated: 09/23/2026, 01:47:41 UTC
Views: 67
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