CVE-2026-24447Network attack vector

Code execution via unescaped CSV formula cells

Published Feb 4, 2026 · Updated Feb 4, 2026

CSV formula injection in Six Apart Movable Type affected releases allows remote authenticated users to embed code in exported CSV files. The CSV export function writes attacker-controlled cell values without escaping leading formula characters, so spreadsheet software interprets them as formulas. Exploitation requires a product user to supply the value and a victim to download and open the CSV; the formula then executes in the victim's environment.

CVSS severity4.8
Medium
EPSS probability0.22%
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 Six Apart Movable Type affected releases allows remote authenticated users to embed code in exported CSV files. The CSV export function writes attacker-controlled cell values without escaping leading formula characters, so spreadsheet software interprets them as formulas. Exploitation requires a product user to supply the value and a victim to download and open the CSV; the formula then executes in the victim's environment.

The record

CVE
CVE-2026-24447
Published
Feb 4, 2026
Updated
Feb 4, 2026
Vendor
Six Apart Ltd.
Product
Movable Type Advanced
Classifications
CWE-1236, T1204.002
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Feb 4, 2026CVE publishedPublication date reported by the CVE source.
  2. Feb 4, 2026Record 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=8.0.2 to 8.0.8 (8.0 series)
  2. Affected versionversion=8.8.0 to 8.8.1 (8.8 series)
  3. Affected versionversion=9.0.4 to 9.0.5 (9.0 series)

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Six Apart Ltd. · Movable Type Advancedversion=8.0.2 to 8.0.8 (8.0 series); version=8.8.0 to 8.8.1 (8.8 series); version=9.0.4 to 9.0.5 (9.0 series)
Six Apart Ltd. · Movable Type Premium (Cloud Edition)version=2.12 (MTP 2 series); version=9.0.5 (9 series)
Six Apart Ltd. · Movable Type Premiumversion=2.13 and earlier (MTP 2 series); version=9.0.4 (MTP 9.0 series)
Six Apart Ltd. · Movable Type Premium (Advanced Edition)version=2.13 and earlier (MTP 2 series); version=9.0.4 (MTP 9.0 series)
Six Apart Ltd. · Movable Typeversion=8.0.2 to 8.0.8 (8.0 series); version=8.8.0 to 8.8.1 (8.8 series); version=9.0.4 to 9.0.5 (9.0 series)
Six Apart Ltd. · Movable Type (Cloud Edition)version=8.8.1 (8 series); version=9.0.5 (9 series)

Published CVSS scores

4.8JPCERT/CCCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:L
6.5JPCERT/CCCVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:L

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 exploitUnconfirmed

Weakness, pattern, technique

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

Public exploit references

No public exploit references are available in this record.

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