SharePoint CVE-2025-49706 Exploitation

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 * Copyright 2025 Google LLC
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 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     https://www.apache.org/licenses/LICENSE-2.0
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 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
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rule ttp_sharepoint_cve_2025_49706_exploitation {

  meta:
    author = "Google Cloud Security"
    rule_name = "SharePoint CVE-2025-49706 Exploitation"
    description = "This rule detects attempts to exploit CVE-2025-49706 in SharePoint by observing POST requests to a vulnerable aspx path, which could result in code execution or server compromise."
    severity = "High"
    tactic = "TA0002"
    technique = "T1210"
    false_positives = "Legitimate administrative actions to the specified URL should be rare. Some penetration testing activity could trigger this rule. In some cases, specific third party applications could generate similar requests, but this should be rare."
    reference = "https://nvd.nist.gov/vuln/detail/CVE-2025-49706, https://research.eye.security/sharepoint-under-siege/"
    rule_id = "mr_661defd1-34e0-47ef-8073-a761244714e3"

 events:
    $e.network.http.method = "POST"
    $e.target.url = /_layouts\/1(5|6)\/ToolPane\.aspx/ nocase
    $e.target.url = /DisplayMode=Edit/ nocase
    $e.target.url = /a=\/ToolPane\.aspx/ nocase
    $e.network.http.referral_url = /^\S*\/_layouts\/1(5|6)\/signout\.aspx(\?.*)?$/ nocase
    $e.network.application_protocol = "HTTP" // Prefilter for HTTP protocol

    $prnc_ip = $e.principal.ip
    $trgt_ip = $e.target.ip

 match:
    $prnc_ip, $trgt_ip over 5m

 outcome:
    $risk_score = max(90)
    $vendor_name = array_distinct($e.metadata.vendor_name)
    $product_name = array_distinct($e.metadata.product_name)
    $result = "attempted"
    $result_time = max($e.metadata.event_timestamp.seconds)
    $target_url = array_distinct($e.target.url)
    $user_agent = array_distinct($e.network.http.user_agent)
    $referrer = array_distinct($e.network.http.referral_url)
    $principal_ip = array($prnc_ip)
    $target_ip = array($trgt_ip)
    $event_count = count($e.metadata.id)
    $target_application = array_distinct($e.target.application)

 condition:
    $e
}