CVE-2026-109506

Status: DeferredMedium (5.9)—PoC

Severity5.9Medium · CVSS 4.0

Exploitation probability0.35 %higher than 27% of CVEs

Active exploitationNonot in the CISA catalog

Public exploitAvailableProof of concept on GitHub (unverified)

Multiple TP-Link Wi-Fi range extenders use a custom, reversible XOR-and-dictionary transformation in the HTTP web-management login flow. An unauthenticated attacker on the same local network who can capture the network traffic associated with legitimate administrator login may be able to derive an alternative credential value that produces the same accepted authentication result and use it to authenticate to the device’s web-management interface with administrator privileges. Exploitation requires the management login to use HTTP and the attacker to observe the session key, dictionary, and login value associated with a legitimate administrator login.

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Successful exploitation may allow an unauthenticated adjacent attacker to gain administrator access to the affected device and modify exposed configuration settings.

CVSS

Base score: 5.9
Version: 4.0
Vector: CVSS:4.0/AV:A/AC:H/AT:N/PR:N/UI:P/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/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

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.35 %
Percentile among all scored CVEs: 27
Score date: 10/20/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Public exploits

Exploit code or detection templates are publicly available. This is not the same as confirmed active exploitation (KEV), but it raises the risk: patch with priority.

Proof of concept on GitHub (unverified) · List of proofs of concept on GitHub

⚠️ GitHub proofs of concept are not verified: some are fake or contain malware. Never run them outside an isolated lab.

ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1203 Exploitation for Client Executionexecution60 %
Primary impactT1078 Valid Accountsstealth · persistence · privilege escalation · initial access55 %

Inferred by deterministic rules from the CVSS vector and CWE. Indicative only.

ATT&CK mitigations that cover these techniques

Application Developer Guidance Active Directory Configuration User Training User Account Management Privileged Account Management Password Policies

CWEs

CWE-287

References

Show 3 references

Raw JSON (NVD)

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    {
      "lang": "en",
      "value": "Multiple\nTP-Link Wi-Fi range extenders use a custom, reversible XOR-and-dictionary\ntransformation in the HTTP web-management login flow. An unauthenticated attacker\non the same local network who can capture the network traffic associated with\nlegitimate administrator login may be able to derive an alternative credential\nvalue that produces the same accepted authentication result and use it to\nauthenticate to the device’s web-management interface with administrator\nprivileges. Exploitation requires the management login to use HTTP and the\nattacker to observe the session key, dictionary, and login value associated\nwith a legitimate administrator login.\n\n\n\n\n\nSuccessful\nexploitation may allow an unauthenticated adjacent attacker to gain\nadministrator access to the affected device and modify exposed configuration\nsettings."
    }
  ],
  "lastModified": "2026-10-15T20:17:06.997",
  "sourceIdentifier": "f23511db-6c3e-4e32-a477-6aa17d310630"
}