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CVE-2026-3622NVD status: Analyzed

TL-WR841N v14: Out-of-bounds Read

CVE-2026-3622 is a high-severity out-of-bounds read vulnerability in TL-WR841N v14 from TP-Link, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 0.9.1 4.19 as the first without the flaw, so updating TL-WR841N v14 to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.35% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update TL-WR841N v14 to 0.9.1 4.19 or a later version.
  2. Update Tl-wr841n Firmware to 0.9.1_4.19 or a later version.
  3. Read the advisory on tp-link.com for workarounds and exact fixed builds.
  4. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
TP-LinkTL-WR841N v14before 0.9.1 4.190.9.1 4.19
TP-LinkTl-wr841n Firmwarebefore 0.9.1_4.190.9.1_4.19

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 4.07.1HighCNA
CVSS 3.17.5HighNVD

Official description

The vulnerability exists in the UPnP component of TL-WR841N v14, where improper input validation leads to an out-of-bounds read, potentially causing a crash of the UPnP service. Successful exploitation can cause the UPnP service to crash, resulting in a Denial-of-Service condition. This vulnerability affects TL-WR841N v14 < EN_0.9.1 4.19 Build 260303 Rel.42399n (V14_260303) and < US_0.9.1.4.19 Build 260312 Rel. 49108n (V14_0304).

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Out-of-bounds Read

The product reads data past the end, or before the beginning, of the intended buffer.

How developers prevent this class of flaw

  • Use a language that provides appropriate memory abstractions.

More Out-of-bounds Read vulnerabilities (CWE-125)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in TL-WR841N v14

All TL-WR841N v14 vulnerabilities

Recent Out-of-bounds Read vulnerabilities

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