CVE-2021-24441Public exploitNetwork attack vector

Command execution via unescaped CSV title

Published Jul 12, 2021 · Updated Aug 3, 2024

CSV injection in the Sign-up Sheets WordPress plugin before 1.0.14 allows remote authenticated users to execute spreadsheet formulas. The CSV exporter writes the stored sheet title into the Title column without neutralizing formula-leading characters, causing spreadsheet software to parse the value as a formula. An authenticated user must create the sheet, and an administrator must export and open the CSV; spreadsheet formula capabilities bound the resulting data access or command execution.

CVSS severity8.0
High
EPSS probability1.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

CSV injection in the Sign-up Sheets WordPress plugin before 1.0.14 allows remote authenticated users to execute spreadsheet formulas. The CSV exporter writes the stored sheet title into the Title column without neutralizing formula-leading characters, causing spreadsheet software to parse the value as a formula. An authenticated user must create the sheet, and an administrator must export and open the CSV; spreadsheet formula capabilities bound the resulting data access or command execution.

The record

CVE
CVE-2021-24441
Published
Jul 12, 2021
Updated
Aug 3, 2024
Vendor
Fetch Designs
Product
Sign-up Sheets
Classifications
CWE-1236, T1204.002
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 12, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record 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=1.0.14 <1.0.14

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Fetch Designs · Sign-up Sheetsversion=1.0.14 <1.0.14

Published CVSS scores

6.0NIST NVDAV:N/AC:M/Au:S/C:P/I:P/A:P
8.0NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/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.

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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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

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

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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