CVE-2021-33259Network attack vector

DNS query history disclosure via unauthenticated interfaces

Published Oct 31, 2021 · Updated Jul 9, 2026

Missing authentication in D-Link DIR-868LW 1.12b web interfaces allows remote attackers to read users' DNS query history. The affected interfaces return stored DNS-query records without first requiring or validating an authenticated session. Network access to the web service is sufficient, and the reported consequence is DNS-history disclosure without configuration changes or service interruption.

CVSS severity5.3
Medium
EPSS probability1.79%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authentication in D-Link DIR-868LW 1.12b web interfaces allows remote attackers to read users' DNS query history. The affected interfaces return stored DNS-query records without first requiring or validating an authenticated session. Network access to the web service is sufficient, and the reported consequence is DNS-history disclosure without configuration changes or service interruption.

The record

CVE
CVE-2021-33259
Published
Oct 31, 2021
Updated
Jul 9, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-306
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Oct 31, 2021CVE publishedPublication date reported by the CVE source.
  2. Jul 9, 2026Record 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 vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
5.0NIST NVDAV:N/AC:L/Au:N/C:P/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.

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No observations available

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

Weakness, pattern, technique

CWE-306Missing Authentication for Critical Function

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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