CVE-2021-37909Network attack vector

Unauthenticated code execution via unchecked registry writes

Published Sep 15, 2021 · Updated Sep 17, 2024

Improper input validation in CHANGING TSSServiSignAdapter 1.0.20.0316 and earlier allows remote attackers to execute arbitrary code. The TSSServiSign component's WriteRegistry function passes attacker-controlled parameters to registry-write operations without filtering or validation. No authentication or user interaction is required; arbitrary registry changes enable execution hijacking.

CVSS severity9.8
Critical
EPSS probability2.01%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in CHANGING TSSServiSignAdapter 1.0.20.0316 and earlier allows remote attackers to execute arbitrary code. The TSSServiSign component's WriteRegistry function passes attacker-controlled parameters to registry-write operations without filtering or validation. No authentication or user interaction is required; arbitrary registry changes enable execution hijacking.

The record

CVE
CVE-2021-37909
Published
Sep 15, 2021
Updated
Sep 17, 2024
Vendor
CHANGING Information Technology Inc.
Product
TSSServiSignAdapter
Classifications
CWE-20, T1210
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 15, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 17, 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=unspecified <=1.0.20.0316

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

CHANGING Information Technology Inc. · TSSServiSignAdapterversion=unspecified <=1.0.20.0316

Published CVSS scores

9.8TWCERT/CCCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5NIST NVDAV:N/AC:L/Au:N/C:P/I:P/A:P

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-20Improper Input Validation
T1210Exploitation of Remote Services

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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