Deserialization of Untrusted Data vulnerability in Sitecore Experience Manager (XM), Sitecore Experience Platform (XP) allows Code Injection.This issue affects Experience Manager (XM): through 9.0; Experience Platform (XP): through 9.0.
https://hackread.com/zero-day-sitecore-exploited-deploy-weepsteel-malware/
https://therecord.media/cisa-orders-patch-for-sitecore-zero-day
https://thehackernews.com/2025/09/cisa-orders-immediate-patch-of-critical.html
https://www.theregister.com/2025/09/04/unknown_miscreants_snooping_around_sitecore/
https://www.securityweek.com/hackers-exploit-sitecore-zero-day-for-malware-delivery/
https://www.infosecurity-magazine.com/news/sitecore-patches-exploited/
https://www.helpnetsecurity.com/2025/09/04/sitecore-zero-day-vulnerability-cve-2025-53690-exploited/
https://www.databreachtoday.com/attackers-exploit-sitecore-zero-day-a-29365
https://www.darkreading.com/vulnerabilities-threats/sitecore-zero-day-viewstate-threats
Published: 2025-09-03
Updated: 2025-09-05
Known Exploited Vulnerability (KEV)
Base Score: 7.6
Vector: CVSS2#AV:N/AC:H/Au:N/C:C/I:C/A:C
Severity: High
Base Score: 9
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
Severity: Critical
EPSS: 0.13496
Tenable Research has classified this CVE under the following Vulnerability Watch classification, which includes active and historical (inactive) classifications. You can learn more about these classifications on our blog.
Vulnerability of Interest