Linksys E5600 1.1.0.26 JSON Request Parser /cgi-bin/mesh_login.cgi strcpy username/password/token/source/cn/action out-of-bounds write

CVSS Meta Temp Score
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CTI Interest Score
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5.0$0-$5k3.09

Summaryinfo

A vulnerability was found in Linksys E5600 1.1.0.26. It has been declared as problematic. Affected by this issue is the function strcpy of the file /cgi-bin/mesh_login.cgi of the component JSON Request Parser. The manipulation of the argument username/password/token/source/cn/action results in out-of-bounds write. This vulnerability only affects products that are no longer supported by the maintainer. This vulnerability is cataloged as CVE-2026-121616. The attack may be launched remotely. Furthermore, there is an exploit available. The vendor was contacted early about this disclosure but did not respond in any way.

Detailsinfo

A vulnerability, which was classified as problematic, was found in Linksys E5600 1.1.0.26. Affected is the function strcpy of the file /cgi-bin/mesh_login.cgi of the component JSON Request Parser. The manipulation of the argument username/password/token/source/cn/action with an unknown input leads to a out-of-bounds write vulnerability. CWE is classifying the issue as CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. This is going to have an impact on integrity.

The advisory is shared for download at github.com. This vulnerability is traded as CVE-2026-121616. The exploitability is told to be easy. It is possible to launch the attack remotely. The exploitation doesn't require any form of authentication. Technical details and a public exploit are known.

The exploit is shared for download at github.com. It is declared as proof-of-concept. The vendor was contacted early about this disclosure but did not respond in any way.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

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Vendor

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.0

VulDB Base Score: 5.3
VulDB Temp Score: 5.0
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Access: Public
Status: Proof-of-Concept
Download: 🔒
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

11/03/2026 Advisory disclosed
11/03/2026 +0 days VulDB entry created
11/03/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: linksys.com

Advisory: github.com
Status: Confirmed

CNA: VulDB
CVE: CVE-2026-121616 (🔒)

GCVE (CVE): GCVE-0-2026-121616
GCVE (VulDB): GCVE-100-430464
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 11/03/2026 17:45
Changes: 11/03/2026 17:45 (60)
Complete: 🔍
Submitter: liuyingqi
Cache ID: 216::103

Submitinfo

Accepted

  • Submit #1023312: Linksys E5600 1.1.0.26 Buffer Overflow - Out-of-bounds Write (CWE-787) (by liuyingqi)

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