CVE-2023-3021Public exploitNetwork attack vector

Authenticated script execution via unsanitized session User-Agent

Published May 31, 2023 · Updated Jan 9, 2025

Stored XSS in I, Librarian before 5.10.4 allows remote authenticated users to execute script in an administrator's browser. The dashboard session table inserts each stored User-Agent string into HTML without applying the application's HTML sanitizer. An attacker must create an authenticated session and an administrator must view the dashboard, exposing data and actions available to that administrator.

CVSS severity5.4
Medium
EPSS probability0.45%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in I, Librarian before 5.10.4 allows remote authenticated users to execute script in an administrator's browser. The dashboard session table inserts each stored User-Agent string into HTML without applying the application's HTML sanitizer. An attacker must create an authenticated session and an administrator must view the dashboard, exposing data and actions available to that administrator.

The record

CVE
CVE-2023-3021
Published
May 31, 2023
Updated
Jan 9, 2025
Vendor
mkucej
Product
I, Librarian
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. May 31, 2023CVE publishedPublication date reported by the CVE source.
  2. Jan 9, 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=unspecified <5.10.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

mkucej · I, Librarianversion=unspecified <5.10.4

Published CVSS scores

4.1huntr.devCVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:N/A:L
5.4NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007Command and Scripting Interpreter: JavaScript

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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