CVE-2021-33842

Authentication bypass via unvalidated cookie parameter

Published Jun 9, 2021 · Updated Sep 16, 2024

Improper authentication in CIRCUTOR SGE-PLC1000 firmware 0.9.2b allows remote attackers to act as authenticated users via a cookie. The device trusts the cookie parameter without validating its integrity, allowing a crafted value to bypass the authenticated-user boundary. Exploitation requires access to the same network as the device; published material does not identify which authenticated operations are reachable.

CVSS severity8.8
High
EPSS probability0.43%
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 CIRCUTOR SGE-PLC1000 firmware 0.9.2b allows remote attackers to act as authenticated users via a cookie. The device trusts the cookie parameter without validating its integrity, allowing a crafted value to bypass the authenticated-user boundary. Exploitation requires access to the same network as the device; published material does not identify which authenticated operations are reachable.

The record

CVE
CVE-2021-33842
Published
Jun 9, 2021
Updated
Sep 16, 2024
Vendor
CIRCUTOR
Product
SGE-PLC1000
Classifications
CWE-565
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 9, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 16, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0.9.2b

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

CIRCUTOR · SGE-PLC1000version=0.9.2b

Published CVSS scores

7.7NVDAV:A/AC:L/Au:S/C:C/I:C/A:C
8.8INCIBECVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-565Reliance on Cookies without Validation and Integrity Checking

Public exploit references

No public exploit references are available in this record.

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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