Linksys E5600 Header upload_fw.cgi init_multipart out-of-bounds write
Summary
| CVE | CVE-2026-121617 |
|---|---|
| State | PUBLISHED |
| Assigner | VulDB |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-11-04 03:17:15 UTC |
| Updated | 2026-11-04 03:17:15 UTC |
| Description | A security flaw has been discovered in Linksys E5600 1.1.0.26. Affected by this issue is the function init_multipart of the file /cgi-bin/upload_fw.cgi of the component Header Parser. The manipulation results in out-of-bounds write. The attack may be launched remotely. The exploit has been released to the public and may be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way. This vulnerability only affects products that are no longer supported by the maintainer. |
Risk And Classification
Primary CVSS: v4.0 7.7 HIGH from [email protected]
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Problem Types: CWE-119 | CWE-787 | CWE-787 Out-of-bounds Write | CWE-119 Memory Corruption
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 4.0 | [email protected] | Secondary | 7.7 | HIGH | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/C... |
| 4.0 | CNA | DECLARED | 8.7 | HIGH | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P |
| 3.1 | [email protected] | Primary | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| 3.1 | CNA | DECLARED | 7.5 | HIGH | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:X/RC:C |
| 3.0 | CNA | DECLARED | 7.5 | HIGH | CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:X/RC:C |
| 2.0 | [email protected] | Secondary | 7.8 | AV:N/AC:L/Au:N/C:N/I:N/A:C | |
| 2.0 | CNA | DECLARED | 7.8 | AV:N/AC:L/Au:N/C:N/I:N/A:C/E:POC/RL:ND/RC:C |
CVSS v4.0 Breakdown
Attack Vector
NetworkAttack Complexity
LowAttack Requirements
NonePrivileges Required
NoneUser Interaction
NoneConfidentiality
NoneIntegrity
NoneAvailability
HighSub Conf.
NoneSub Integrity
NoneSub Availability
NoneCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
CVSS v3.1 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
NoneAvailability
HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v3.0 Breakdown
Attack Vector
NetworkAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
NoneIntegrity
NoneAvailability
HighCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:X/RC:C
Vendor Declared Affected Products
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| vuldb.com/vuln/430465/cti | [email protected] | vuldb.com | |
| vuldb.com/vuln/430465 | [email protected] | vuldb.com | |
| vuldb.com/submit/1023313 | [email protected] | vuldb.com | |
| github.com/Zimo-666/E5600-cves/tree/main/04-upload-fw-multipart-overflow | [email protected] | github.com | |
| www.linksys.com | [email protected] | www.linksys.com | |
| vuldb.com/cve/CVE-2026-121617 | [email protected] | vuldb.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: liuyingqi (VulDB User) (en)
CNA: VulDB CNA Team (en)
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| CNA | 2026-11-03T00:00:00.000Z | Advisory disclosed |
| CNA | 2026-11-03T01:00:00.000Z | VulDB entry created |
| CNA | 2026-11-03T17:45:17.000Z | VulDB entry last update |
There are currently no legacy QID mappings associated with this CVE.