CVE-2020-18698Network attack vector

Account compromise via unrestricted login attempts

Published Aug 16, 2021 · Updated Aug 4, 2024

Improper login-attempt restriction in Lin-CMS-Flask 0.1.1 allows remote attackers to brute-force account passwords through its login API. The login() function in app/api/cms/user.py accepts repeated credential submissions without throttling, lockout, or a verification challenge. The endpoint requires no prior authentication; compromise still depends on guessing a valid username and password, after which the account's access is exposed.

CVSS severity9.8
Critical
EPSS probability2.04%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper login-attempt restriction in Lin-CMS-Flask 0.1.1 allows remote attackers to brute-force account passwords through its login API. The login() function in app/api/cms/user.py accepts repeated credential submissions without throttling, lockout, or a verification challenge. The endpoint requires no prior authentication; compromise still depends on guessing a valid username and password, after which the account's access is exposed.

The record

CVE
CVE-2020-18698
Published
Aug 16, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-307, CAPEC-49, T1110.001
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 16, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 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
9.3GitHubCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
9.8NIST NVDCVSS:3.1/AV:N/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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-307Improper Restriction of Excessive Authentication Attempts
CAPEC-49Password Brute Forcing
T1110.001Password Guessing

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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