CVE-2025-9100Public exploitNetwork attack vector

Comment flooding via reusable CAPTCHA verification

Published Aug 18, 2025 · Updated Aug 18, 2025

Authentication bypass in ZHENFENG13's blogging application 1.0.0 allows remote attackers to flood comments with a reused CAPTCHA response. The /blog/comment handler accepts the same verification code repeatedly instead of refreshing or invalidating it after submission. No authentication is required; repeated comment posts can exhaust database resources and interrupt the service.

CVSS severity5.3
Medium
EPSS probability0.55%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Authentication bypass in ZHENFENG13's blogging application 1.0.0 allows remote attackers to flood comments with a reused CAPTCHA response. The /blog/comment handler accepts the same verification code repeatedly instead of refreshing or invalidating it after submission. No authentication is required; repeated comment posts can exhaust database resources and interrupt the service.

The record

CVE
CVE-2025-9100
Published
Aug 18, 2025
Updated
Aug 18, 2025
Vendor
ZHENFENG13
Product
My-Blog
Classifications
CWE-287, CWE-294, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 18, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 18, 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?

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

  1. Affected versionversion=1.0.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

ZHENFENG13 · My-Blogversion=1.0.0

Published CVSS scores

3.7NIST NVDCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
5.3VulDBCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
5.0VulDBAV:N/AC:L/Au:N/C:N/I:P/A:N
5.5VulDBCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E: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.

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 exploitPublished

Weakness, pattern, technique

CWE-287Improper Authentication
CWE-294Authentication Bypass by Capture-replay
T1499Endpoint Denial of Service

Public exploit references

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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