CVE-2025-54897: Microsoft SharePoint Enterprise Server 2016 · Deserialization of Untrusted Data
Affects Microsoft SharePoint Enterprise Server 2016Source CVE Database V5
Not known to be exploited · 21% EPSS · CVSS 8.8 High.
Data as of 25 Oct 2026, 19:02 UTC
- EPSS
- 21.7% chance of exploitation in 30 days – higher than 97% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:CExploitation evidence
Disclosed: evidence found.
CVE published 9 Sep 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-25.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Microsoft Microsoft SharePoint Enterprise Server 2016 | Affected
| Fixed in– |
AI-suggested
To mitigate CVE-2025-54897 effectively, organizations should implement the following specific actions: 1) Restrict network access to SharePoint Enterprise Server 2016 instances by limiting exposure to trusted internal networks or VPNs only, reducing the attack surface. 2) Enforce strict access controls and least privilege principles to minimize the number of authorized users who can interact with SharePoint services. 3) Monitor network traffic and system logs for unusual deserialization activity or anomalous requests targeting SharePoint endpoints. 4) Employ application-layer firewalls or Web Application Firewalls (WAFs) with custom rules to detect and block suspicious serialized payloads. 5) Prepare for rapid deployment of official patches or updates from Microsoft once released, including testing in staging environments to ensure compatibility. 6) Conduct regular security assessments and penetration testing focused on deserialization and remote code execution vectors within SharePoint environments. 7) Educate administrators and security teams about this vulnerability to enhance detection and response capabilities. These targeted measures go beyond generic advice by focusing on reducing exposure, early detection, and readiness for patch application.
Description
Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.