CVE-2023-33653Public exploitNetwork attack vector

Authenticated code execution via unsafe HTML deserialization

Published Jun 6, 2023 · Updated Jan 8, 2025

Unsafe deserialization in Sitecore Experience Platform 9.3 allows remote authenticated users to execute arbitrary code through crafted HTML. The ConvertToRuntimeHtml ConvertWebControls processor extracts a value attribute from an scInlineControl element, base64-decodes it, and passes the bytes to BinaryFormatter.Deserialize without validation. A valid Sitecore session is required to reach the Content Manager Execute.aspx conversion endpoint, after which a crafted object graph runs code in the web-server process.

CVSS severity8.8
High
EPSS probability2.09%
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

Unsafe deserialization in Sitecore Experience Platform 9.3 allows remote authenticated users to execute arbitrary code through crafted HTML. The ConvertToRuntimeHtml ConvertWebControls processor extracts a value attribute from an scInlineControl element, base64-decodes it, and passes the bytes to BinaryFormatter.Deserialize without validation. A valid Sitecore session is required to reach the Content Manager Execute.aspx conversion endpoint, after which a crafted object graph runs code in the web-server process.

The record

CVE
CVE-2023-33653
Published
Jun 6, 2023
Updated
Jan 8, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 6, 2023CVE publishedPublication date reported by the CVE source.
  2. Jan 8, 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?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
8.8NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/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 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

T1190Exploit Public-Facing Application

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