CVE-2023-47102Public exploitNetwork attack vector

Account enumeration via distinguishable login errors

Published Nov 7, 2023 · Updated Sep 29, 2025

User enumeration in UrBackup Server 2.5.31 allows remote attackers to identify valid accounts through the unauthenticated login interface. The /x?a=login workflow returns “User does not exist” for unknown names but “Wrong password” for existing accounts, exposing account validity. No account or user interaction is required, and disclosed automation can use confirmed usernames for password guessing.

CVSS severity5.3
Medium
EPSS probability0.63%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

User enumeration in UrBackup Server 2.5.31 allows remote attackers to identify valid accounts through the unauthenticated login interface. The /x?a=login workflow returns “User does not exist” for unknown names but “Wrong password” for existing accounts, exposing account validity. No account or user interaction is required, and disclosed automation can use confirmed usernames for password guessing.

The record

CVE
CVE-2023-47102
Published
Nov 7, 2023
Updated
Sep 29, 2025
Vendor
UrBackup
Product
UrBackup Server
Classifications
CWE-203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Nov 7, 2023CVE publishedPublication date reported by the CVE source.
  2. Sep 29, 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=2.5.31

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

UrBackup · UrBackup Serverversion=2.5.31

Published CVSS scores

5.3CISA ADP VulnrichmentCVSS: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.

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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-203Observable Discrepancy

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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