CVE-2021-33484Public exploitNetwork attack vector

Unauthenticated user spoofing via recoverable encryption key

Published Sep 7, 2021 · Updated Aug 3, 2024

Improper authentication in OnyakTech Comments Pro 3.8 allows remote attackers to spoof users in unauthenticated comment posts. CommentsService.ashx decrypts the request's encrypted key when it is supplied as the display name, while the installer exposes a hardcoded IV and the encryption routine. Combining the recovered key and IV lets an attacker forge another user's encrypted name and identifier, then post or delete comments as that user without authentication.

CVSS severity7.5
High
EPSS probability0.89%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authentication in OnyakTech Comments Pro 3.8 allows remote attackers to spoof users in unauthenticated comment posts. CommentsService.ashx decrypts the request's encrypted key when it is supplied as the display name, while the installer exposes a hardcoded IV and the encryption routine. Combining the recovered key and IV lets an attacker forge another user's encrypted name and identifier, then post or delete comments as that user without authentication.

The record

CVE
CVE-2021-33484
Published
Sep 7, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-798, T1606
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 7, 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 vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.0NIST NVDAV:N/AC:L/Au:N/C:P/I:N/A:N
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-798Use of Hard-coded Credentials
T1606Forge Web Credentials

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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