{"id":53319,"date":"2025-06-18T09:31:22","date_gmt":"2025-06-18T09:31:22","guid":{"rendered":""},"modified":"2025-09-08T17:18:48","modified_gmt":"2025-09-08T23:18:48","slug":"cve-2025-47166-critical-deserialization-vulnerability-in-microsoft-office-sharepoint","status":"publish","type":"post","link":"https:\/\/www.ameeba.com\/blog\/cve-2025-47166-critical-deserialization-vulnerability-in-microsoft-office-sharepoint\/","title":{"rendered":"<strong>CVE-2025-47166: Critical Deserialization Vulnerability in Microsoft Office SharePoint<\/strong>"},"content":{"rendered":"<p><strong>Overview<\/strong><\/p>\n<p>The cybersecurity landscape is riddled with a multitude of vulnerabilities that can lead to potential system compromise or data leakage. One such vulnerability, designated as CVE-2025-47166, has been identified in Microsoft Office SharePoint. This <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-49072-deserialization-of-untrusted-data-vulnerability-in-ancorathemes-mr-murphy\/\"  data-wpil-monitor-id=\"59704\">vulnerability stems from the deserialization of untrusted data<\/a>, allowing an authorized attacker to execute code over a network. Notably, this <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-49261-high-impact-remote-file-inclusion-vulnerability-in-themebay-s-diza\/\"  data-wpil-monitor-id=\"63786\">vulnerability impacts<\/a> numerous organizations worldwide that leverage SharePoint for their business operations. It is vital for these organizations to understand and address this <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-47827-critical-security-vulnerability-in-igel-os-allows-secure-boot-bypass\/\"  data-wpil-monitor-id=\"59871\">critical security<\/a> flaw to mitigate potential cyber threats.<\/p>\n<p><strong>Vulnerability Summary<\/strong><\/p>\n<p>CVE ID: CVE-2025-47166<br \/>\nSeverity: Critical (8.8 CVSS Score)<br \/>\nAttack Vector: Network<br \/>\nPrivileges Required: Low<br \/>\nUser Interaction: Required<br \/>\nImpact: <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-31222-potential-privilege-elevation-and-system-compromise-vulnerability\/\"  data-wpil-monitor-id=\"59692\">Potential system compromise<\/a> or data leakage<\/p>\n<p><strong>Affected Products<\/strong><\/p><div id=\"ameeb-1742318032\" class=\"ameeb-content-2 ameeb-entity-placement\"><div style=\"border-left: 4px solid #555; padding-left: 20px; margin: 48px 0; font-family: Roboto, sans-serif; color: #ffffff; line-height: 1.6; max-width: 720px;\">\r\n  <h2 style=\"margin-top: 0; font-size: 22px; font-weight: 600; display: flex; align-items: center; letter-spacing: -0.02em;\">\r\n    <a href=\"https:\/\/www.ameeba.com\/chat\" style=\"display: inline-flex; align-items: center; margin-right: 10px;\">\r\n      <img decoding=\"async\" src=\"https:\/\/www.ameeba.com\/blog\/wp-content\/uploads\/2025\/10\/Best-App-icon-Ameeba.png\" alt=\"Ameeba Chat Icon\" style=\"width: 42px; height: 42px;\" \/>\r\n    <\/a>\r\n    Share secrets securely\r\n  <\/h2>\r\n\r\n  <p style=\"margin-bottom: 14px; color: #d1d5db;\">\r\n    Ameeba is private infrastructure for communication and sensitive work built on encrypted identity instead of exposed corporate identity systems.\r\n  <\/p>\r\n\r\n  <p style=\"margin-bottom: 18px; color: #a1a1aa;\">\r\n    Passwords, credentials, confidential files, screenshots, internal discussions, sensitive AI context, and private coordination should not become exposed across ordinary communication platforms.\r\n  <\/p>\r\n\r\n  <ul style=\"list-style: none; padding-left: 0; margin-bottom: 24px; color: #e4e4e7;\">\r\n    <li style=\"margin-bottom: 8px;\">\u2022 Encrypted identity<\/li>\r\n    <li style=\"margin-bottom: 8px;\">\u2022 Private Spaces for organizations and teams<\/li>\r\n    <li style=\"margin-bottom: 8px;\">\u2022 End-to-end encrypted chat, calls, files, and notes<\/li>\r\n    <li style=\"margin-bottom: 8px;\">\u2022 Sensitive AI work and protected collaboration<\/li>\r\n    <li>\u2022 Built for information that cannot leak<\/li>\r\n  <\/ul>\r\n\r\n  <p style=\"font-style: italic; font-weight: 600; margin-bottom: 24px; color: #ffffff;\">\r\n    Our mission is to secure human work alongside AI.\r\n  <\/p>\r\n\r\n  <div style=\"display: flex; flex-wrap: wrap; gap: 12px;\">\r\n    <a href=\"https:\/\/www.ameeba.com\/chat\/download\" style=\"background-color: #ffffff; color: #000000; padding: 10px 20px; text-decoration: none; border-radius: 8px; font-weight: 500;\">\r\n      Download Ameeba\r\n    <\/a>\r\n\r\n    <a href=\"https:\/\/www.ameeba.com\/chat\" style=\"border: 1px solid #ffffff; color: #ffffff; padding: 10px 20px; text-decoration: none; border-radius: 8px; font-weight: 500;\">\r\n      Learn More\r\n    <\/a>\r\n  <\/div>\r\n<\/div><\/div>\n<p>Product | Affected Versions<\/p>\n<p><a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-47163-unauthorized-code-execution-through-microsoft-sharepoint-deserialization-vulnerability\/\"  data-wpil-monitor-id=\"60960\">Microsoft Office SharePoint<\/a> | [Assumed all versions until specific data available]<\/p>\n<p><strong>How the Exploit Works<\/strong><\/p>\n<p>The exploit leverages the <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-47584-critical-deserialization-of-untrusted-data-vulnerability-in-themegoods-photography\/\"  data-wpil-monitor-id=\"59892\">deserialization vulnerability<\/a> in Microsoft Office SharePoint. Deserialization is the process of converting a stream of bytes back into a copy of the original object. In this case, an authorized attacker can insert malicious serialized data that, when deserialized, can <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-3835-remote-code-execution-vulnerability-in-zohocorp-manageengine-exchange-reporter-plus\/\"  data-wpil-monitor-id=\"59861\">execute arbitrary code<\/a>. This is possible because SharePoint does not correctly validate or sanitize the serialized data it receives over the network.<\/p>\n<p><strong>Conceptual Example Code<\/strong><\/p><div id=\"ameeb-400837246\" class=\"ameeb-content ameeb-entity-placement\"><div class=\"poptin-embedded\" data-id=\"f6b387694f681\"><\/div>\r\n\r\n\r\n\r\n\r\n\r\n<\/div>\n<p>The following is a conceptual representation of how the vulnerability might be exploited. This hypothetical HTTP request could be sent by an <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-5353-local-authenticated-attacker-exploit-in-ivanti-workspace-control\/\"  data-wpil-monitor-id=\"60961\">attacker to exploit<\/a> the vulnerability:<\/p>\n<pre><code class=\"\" data-line=\"\">POST \/SharePoint\/endpoint HTTP\/1.1\nHost: target.example.com\nContent-Type: application\/serialized-object\n{ &quot;serialized_object&quot;: &quot;base64_encoded_malicious_object&quot; }<\/code><\/pre>\n<p>In this case, `base64_encoded_malicious_object` represents a serialized object that contains <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-8714-critical-postgresql-vulnerability-allowing-malicious-code-injection-by-superusers\/\"  data-wpil-monitor-id=\"80686\">malicious code<\/a>. When the SharePoint server deserializes this object, it could potentially execute the embedded malicious code, <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-21475-critical-memory-corruption-vulnerability-leading-to-potential-system-compromise\/\"  data-wpil-monitor-id=\"59912\">leading to a system<\/a> compromise or data leakage.<\/p>\n<p><strong>Mitigation Guidance<\/strong><\/p>\n<p>While <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-47172-sql-injection-vulnerability-in-microsoft-office-sharepoint\/\"  data-wpil-monitor-id=\"61096\">Microsoft<\/a> is likely to release a patch to address this vulnerability, organizations are advised to apply the vendor patch as soon as it is available. As an interim measure, organizations could employ a Web Application Firewall (WAF) or Intrusion Detection System (IDS) to detect and prevent exploitation attempts. Other best practices include restricting network <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-52571-unauthenticated-access-to-telegram-account-and-server-via-hikka-userbot\/\"  data-wpil-monitor-id=\"64502\">access to the SharePoint server<\/a> and regularly updating all software components.<br \/>\nRemember, staying <a href=\"https:\/\/www.ameeba.com\/blog\/cve-2025-5243-critical-security-vulnerability-in-smg-software-information-portal\/\"  data-wpil-monitor-id=\"67980\">informed about the latest cybersecurity threats and implementing appropriate security<\/a> measures is crucial for maintaining a secure IT environment.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Overview The cybersecurity landscape is riddled with a multitude of vulnerabilities that can lead to potential system compromise or data leakage. One such vulnerability, designated as CVE-2025-47166, has been identified in Microsoft Office SharePoint. This vulnerability stems from the deserialization of untrusted data, allowing an authorized attacker to execute code over a network. Notably, this [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"footnotes":""},"categories":[1],"tags":[],"vendor":[82],"product":[],"attack_vector":[],"asset_type":[],"severity":[],"exploit_status":[],"class_list":["post-53319","post","type-post","status-publish","format-standard","hentry","category-uncategorized","vendor-microsoft"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/53319","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/comments?post=53319"}],"version-history":[{"count":12,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/53319\/revisions"}],"predecessor-version":[{"id":73113,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/posts\/53319\/revisions\/73113"}],"wp:attachment":[{"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/media?parent=53319"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/categories?post=53319"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/tags?post=53319"},{"taxonomy":"vendor","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/vendor?post=53319"},{"taxonomy":"product","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/product?post=53319"},{"taxonomy":"attack_vector","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/attack_vector?post=53319"},{"taxonomy":"asset_type","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/asset_type?post=53319"},{"taxonomy":"severity","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/severity?post=53319"},{"taxonomy":"exploit_status","embeddable":true,"href":"https:\/\/www.ameeba.com\/blog\/wp-json\/wp\/v2\/exploit_status?post=53319"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}