CVE-2020-3935Network attack vector

Password disclosure via cleartext authentication cookies

Published Feb 11, 2020 · Updated Sep 16, 2024

Cleartext storage in Taiwan Secom access and attendance systems allows remote attackers to obtain passwords from client cookies. The applications write users' password information directly into client-side cookies without encryption instead of retaining only opaque session identifiers. No authentication or user interaction is required; the documented consequence is password disclosure, with no reported data modification or service interruption.

CVSS severity7.5
High
EPSS probability0.93%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cleartext storage in Taiwan Secom access and attendance systems allows remote attackers to obtain passwords from client cookies. The applications write users' password information directly into client-side cookies without encryption instead of retaining only opaque session identifiers. No authentication or user interaction is required; the documented consequence is password disclosure, with no reported data modification or service interruption.

The record

CVE
CVE-2020-3935
Published
Feb 11, 2020
Updated
Sep 16, 2024
Vendor
Taiwan Secom Co., Ltd.
Product
Personnel Attendance Management System
Classifications
CWE-312
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 11, 2020CVE 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 <=3.3.0.3_20160517

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Taiwan Secom Co., Ltd. · Personnel Attendance Management Systemversion=0 <=3.3.0.3_20160517
Taiwan Secom Co., Ltd. · Integrated Access Controlversion=0 <=3.3.2

Published CVSS scores

7.5TWCERT/CCCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
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 exploitUnconfirmed

Weakness, pattern, technique

CWE-312Cleartext Storage of Sensitive Information

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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