CVE-2021-28858Public exploit

Sensitive-data exposure via default cleartext management traffic

Published Jun 15, 2021 · Updated Aug 3, 2024

Cleartext transmission in the web interface of TP-Link TL-WPA4220 4.0.2 Build 20180308 Rel.37064 allows remote attackers to capture data. The management interface uses HTTP rather than SSL by default, exposing session cookies and other sensitive information to passive traffic monitoring. An attacker must share the device's local network and observe management traffic; the disclosed impact is limited to confidentiality loss.

CVSS severity5.5
Medium
EPSS probability0.26%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cleartext transmission in the web interface of TP-Link TL-WPA4220 4.0.2 Build 20180308 Rel.37064 allows remote attackers to capture data. The management interface uses HTTP rather than SSL by default, exposing session cookies and other sensitive information to passive traffic monitoring. An attacker must share the device's local network and observe management traffic; the disclosed impact is limited to confidentiality loss.

The record

CVE
CVE-2021-28858
Published
Jun 15, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-312, T1040
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 15, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

2.1NIST National Vulnerability DatabaseAV:L/AC:L/Au:N/C:P/I:N/A:N
5.5NIST National Vulnerability DatabaseCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-312Cleartext Storage of Sensitive Information
T1040Network Sniffing

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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