CVE-2023-31286Public exploitNetwork attack vector

User enumeration via distinct password-reset responses

Published Apr 27, 2023 · Updated Feb 13, 2025

User enumeration in Serenity Serene and StartSharp before 6.7.0 allows remote attackers to identify registered email addresses. POST requests to /Account/ForgotPassword return a 400 CantFindUserWithEmail error for an unknown address but a 200 response for an existing account. The endpoint requires no authentication, and the disclosure makes password-guessing attacks more efficient.

CVSS severity5.3
Medium
EPSS probability1.01%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

User enumeration in Serenity Serene and StartSharp before 6.7.0 allows remote attackers to identify registered email addresses. POST requests to /Account/ForgotPassword return a 400 CantFindUserWithEmail error for an unknown address but a 200 response for an existing account. The endpoint requires no authentication, and the disclosure makes password-guessing attacks more efficient.

The record

CVE
CVE-2023-31286
Published
Apr 27, 2023
Updated
Feb 13, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-209, T1087
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 27, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 13, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

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

5.3CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/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 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-209Generation of Error Message Containing Sensitive Information
T1087Account Discovery

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo