{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","feed_url":"https://feed.craftedsignal.io/products/sharepoint-server-2019/feed.json","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cpes":[],"_cs_cves":[],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["SharePoint Enterprise Server 2016","SharePoint Server 2019","SharePoint Server Subscription Edition"],"_cs_severities":["critical"],"_cs_tags":["cve-2026-45659","rce","sharepoint","remote code execution","vulnerability"],"_cs_type":"threat","_cs_vendors":["Microsoft"],"content_html":"\u003cp\u003eA critical remote code execution (RCE) vulnerability, identified as CVE-2026-45659, has been discovered in Microsoft SharePoint products. This vulnerability affects SharePoint Enterprise Server 2016, SharePoint Server 2019, and SharePoint Server Subscription Edition. Successful exploitation of this vulnerability allows an unauthenticated attacker to execute arbitrary code on the target system. The vulnerability was disclosed in a Microsoft Security Bulletin on May 21, 2026. It is crucial for organizations using affected versions of SharePoint to apply the necessary patches as soon as possible to mitigate the risk of exploitation. Given the widespread use of SharePoint in enterprise environments, this vulnerability poses a significant threat.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAn unauthenticated attacker sends a specially crafted request to a vulnerable SharePoint server.\u003c/li\u003e\n\u003cli\u003eThe request exploits a flaw in the way SharePoint processes specific types of data.\u003c/li\u003e\n\u003cli\u003eThis leads to the execution of arbitrary code within the context of the SharePoint application pool.\u003c/li\u003e\n\u003cli\u003eThe attacker gains control over the SharePoint server.\u003c/li\u003e\n\u003cli\u003eThe attacker leverages the initial access to move laterally within the network.\u003c/li\u003e\n\u003cli\u003eThe attacker compromises other systems and resources within the organization\u0026rsquo;s environment.\u003c/li\u003e\n\u003cli\u003eThe attacker installs a webshell for persistent access.\u003c/li\u003e\n\u003cli\u003eThe final objective is to exfiltrate sensitive data or deploy ransomware.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eSuccessful exploitation of CVE-2026-45659 can lead to complete compromise of the SharePoint server and potentially the entire network. An attacker can gain unauthorized access to sensitive data, disrupt services, or deploy malicious payloads like ransomware. Given the widespread use of SharePoint for document management and collaboration, this vulnerability poses a significant risk to organizations across various sectors. If exploited, this vulnerability allows remote code execution, potentially leading to data breaches, system downtime, and financial losses.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eApply the patches provided in the Microsoft Security Bulletin CVE-2026-45659 to remediate the remote code execution vulnerability on all affected SharePoint servers.\u003c/li\u003e\n\u003cli\u003eDeploy the Sigma rule \u003ccode\u003eDetect CVE-2026-45659 Exploitation Attempt via HTTP Request\u003c/code\u003e to detect potential exploitation attempts.\u003c/li\u003e\n\u003cli\u003eMonitor web server logs for suspicious HTTP requests targeting SharePoint servers as described in the Attack Chain.\u003c/li\u003e\n\u003cli\u003eImplement network segmentation to limit the potential impact of a successful exploitation as mentioned in the attack chain, specifically lateral movement.\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-05-22T13:05:32Z","date_published":"2026-05-22T13:05:32Z","id":"https://feed.craftedsignal.io/briefs/2026-05-sharepoint-rce/","summary":"A remote code execution vulnerability, tracked as CVE-2026-45659, affects Microsoft SharePoint Enterprise Server 2016, SharePoint Server 2019, and SharePoint Server Subscription Edition, allowing an attacker to execute arbitrary code remotely.","title":"Microsoft SharePoint Remote Code Execution Vulnerability (CVE-2026-45659)","url":"https://feed.craftedsignal.io/briefs/2026-05-sharepoint-rce/"}],"language":"en","title":"CraftedSignal Threat Feed — SharePoint Server 2019","version":"https://jsonfeed.org/version/1.1"}