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Fencer Intel
medium 5.3

CVE-2026-76651 json

Pre-Authentication Multipart Boundary Buffer Overflow in HTTP Service in TP-Link TL-WR841N

published 2mo ago modified 2mo ago also EUVD-2026-67937

cvss
5.3
version 4.0, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.4%
EPSS 0.4% chance of exploitation in 30 days, percentile 39%
public exploits
0
none known

Summary

A buffer overflow vulnerability exists in the embedded HTTP service in TL-WR841N v14 when processing multipart/form-data requests. Insufficient validation of an attacker-controlled boundary parameter may allow a remote unauthenticated attacker to submit a crafted request that corrupts memory by overwriting data beyond the bounds of an internal buffer.

Successful exploitation may result in modification or corruption of process memory, potentially leading to undefined application behavior. Arbitrary code execution, information disclosure, and denial-of-service conditions have not been demonstrated.

Patch / fix

  • TP-Link System Inc. TL-WR841N v14 TL-WR841N(EU)_V14_4.19 Build 260821 Rel.56588, TL-WR841N(US)_V14_4.19 Build 260820 Rel.33478

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CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
2mo ago

Exploit prediction

0.44% chance of exploitation in the next 30 days, higher than 39% of all scored CVEs (FIRST EPSS, 2026-11-11).

CVSS scores

assigned by version score vector
CNA 4.0 5.3 CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
CNA 4.0 5.3 CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/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

Affected products

  • TP-Link System Inc. TL-WR841N v14

Classification

Weakness
  • CWE-120 Buffer Copy without Checking Size of Input

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.