CVE-2025-53691Public exploitNetwork attack vector

Authenticated remote code execution via unrestricted BinaryFormatter deserialization

Published Sep 3, 2025 · Updated Sep 3, 2025

Untrusted deserialization in Sitecore XM and XP 9.0 through 9.3 and 10.0 through 10.4 allows remote authenticated users to execute code. The ConvertWebControls pipeline passes a base64 value from attacker-supplied HTML to Sitecore.Convert.Base64ToObject, which invokes BinaryFormatter.Deserialize without a binder or type checks. Content Editor rights are required; successful exploitation runs attacker-chosen code in the Sitecore server process.

CVSS severity8.8
High
EPSS probability1.54%
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

Untrusted deserialization in Sitecore XM and XP 9.0 through 9.3 and 10.0 through 10.4 allows remote authenticated users to execute code. The ConvertWebControls pipeline passes a base64 value from attacker-supplied HTML to Sitecore.Convert.Base64ToObject, which invokes BinaryFormatter.Deserialize without a binder or type checks. Content Editor rights are required; successful exploitation runs attacker-chosen code in the Sitecore server process.

The record

CVE
CVE-2025-53691
Published
Sep 3, 2025
Updated
Sep 3, 2025
Vendor
Sitecore
Product
Sitecore Experience Manager
Classifications
CWE-502, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Sep 3, 2025CVE publishedPublication date reported by the CVE source.
  2. Sep 3, 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=10.0 <=10.4
  2. Affected versionversion=9.0 <=9.3

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Sitecore · Sitecore Experience Managerversion=10.0 <=10.4; version=9.0 <=9.3
Sitecore · Sitecore Experience Platformversion=10.0 <=10.4; version=9.0 <=9.3

Published CVSS scores

8.8WizCVSS: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

CWE-502Deserialization of Untrusted Data
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