CVE-2023-28821Network attack vector

Unauthenticated service interruption via unthrottled password resets

Published Apr 28, 2023 · Updated Jan 30, 2025

Missing rate limiting in Concrete CMS before 9.1 allows remote attackers to interrupt service through repeated password-reset requests. The public password-reset endpoint accepts repeated unauthenticated reset submissions without throttling, allowing request-processing resources to be consumed. No account or user interaction is required, and the published impact is limited to reduced service availability rather than data access or modification.

CVSS severity5.3
Medium
EPSS probability0.73%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing rate limiting in Concrete CMS before 9.1 allows remote attackers to interrupt service through repeated password-reset requests. The public password-reset endpoint accepts repeated unauthenticated reset submissions without throttling, allowing request-processing resources to be consumed. No account or user interaction is required, and the published impact is limited to reduced service availability rather than data access or modification.

The record

CVE
CVE-2023-28821
Published
Apr 28, 2023
Updated
Jan 30, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-640, T1499.003
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 28, 2023CVE publishedPublication date reported by the CVE source.
  2. Jan 30, 2025Record 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

5.3Concrete CMS Security TeamCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

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-640Weak Password Recovery Mechanism for Forgotten Password
T1499.003Application Exhaustion Flood

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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