CVE-2023-2258Public exploitNetwork attack vector

Spreadsheet formula execution via unescaped CSV fields

Published Apr 24, 2023 · Updated Feb 4, 2025

CSV formula injection in alf.io before 2.0-M4-2304 allows remote attackers to execute spreadsheet formulas through exported event data. ExportUtils.exportCsv passes every generated data cell directly to CSVWriter without neutralizing fields that begin with =, +, -, or @. Exploitation requires a recipient to export attacker-controlled values and open the file in formula-evaluating spreadsheet software, where the formula runs with that recipient's spreadsheet permissions.

CVSS severity8.8
High
EPSS probability0.91%
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

CSV formula injection in alf.io before 2.0-M4-2304 allows remote attackers to execute spreadsheet formulas through exported event data. ExportUtils.exportCsv passes every generated data cell directly to CSVWriter without neutralizing fields that begin with =, +, -, or @. Exploitation requires a recipient to export attacker-controlled values and open the file in formula-evaluating spreadsheet software, where the formula runs with that recipient's spreadsheet permissions.

The record

CVE
CVE-2023-2258
Published
Apr 24, 2023
Updated
Feb 4, 2025
Vendor
Alf.io
Product
alf.io
Classifications
CWE-1236, T1204.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 24, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 4, 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?

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

  1. Affected versionversion=unspecified <2.0-M4-2304

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Alf.io · alf.ioversion=unspecified <2.0-M4-2304

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
8.8huntr.devCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-1236Improper Neutralization of Formula Elements in a CSV File
T1204.002User Execution: Malicious File

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