CVE-2023-45746Network attack vector

Authenticated script execution via unneutralized mt.cgi output

Published Oct 30, 2023 · Updated Oct 29, 2024

Cross-site scripting in affected Six Apart Movable Type editions allows remote authenticated users to inject arbitrary script. The flaws reside in mt.cgi, but Six Apart has not disclosed which parameters or output contexts fail to neutralize attacker-controlled content. Exploitation requires authenticated input and a logged-in user to load an affected page, executing the script in that user's browser.

CVSS severity5.4
Medium
EPSS probability0.35%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in affected Six Apart Movable Type editions allows remote authenticated users to inject arbitrary script. The flaws reside in mt.cgi, but Six Apart has not disclosed which parameters or output contexts fail to neutralize attacker-controlled content. Exploitation requires authenticated input and a logged-in user to load an affected page, executing the script in that user's browser.

The record

CVE
CVE-2023-45746
Published
Oct 30, 2023
Updated
Oct 29, 2024
Vendor
Six Apart Ltd.
Product
Movable Type Advanced
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 30, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 29, 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=r.5405 and earlier

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Six Apart Ltd. · Movable Type Advancedversion=r.5405 and earlier
Six Apart Ltd. · Movable Type Premium (Cloud Edition)version=1.58 and earlier
Six Apart Ltd. · Movable Type Premiumversion=1.58 and earlier
Six Apart Ltd. · Movable Type Premium (Advanced Edition)version=1.58 and earlier
Six Apart Ltd. · Movable Typeversion=r.5405 and earlier
Six Apart Ltd. · Movable Type (Cloud Edition)version=r.5405 and earlier

Published CVSS scores

3.5JPCERT/CCAV:N/AC:M/Au:S/C:N/I:P/A:N
5.4CISA-ADPCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
5.4JPCERT/CCCVSS:3.0/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

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

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

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Your stack

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