cbcvebase.
CVE-2023-32563
published 2023-08-10

CVE-2023-32563: An unauthenticated attacker could achieve the code execution through a RemoteControl server.

PriorityP194critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
ITWEXPLOITVulnCheck KEV
Exploited in the wild
EPSS
90.17%
99.8th percentile
An unauthenticated attacker could achieve the code execution through a RemoteControl server.

Affected

1 ranges
VendorProductVersion rangeFixed in
ivantiavalanche< 6.4.16.4.1

Detection & IOCsextracted from sources · hover to see the quote

urlPOST /Servlet/Skins HTTP/1.1
path/Servlet/Skins
path../../../Web/webapps/ROOT
filename{{randstr}}.jsp
  • Exploit sends a multipart POST to /Servlet/Skins with a path-traversal 'guid' field value of '../../../Web/webapps/ROOT' to drop a JSP webshell into the Tomcat ROOT directory.
  • The 'guid' multipart field is abused for directory traversal; monitor for values containing '../' sequences targeting web application directories.
  • After upload, attacker performs a GET request to the dropped JSP file at the web root to trigger remote code execution; monitor for GET requests to newly created .jsp files at the root path.
  • Exploitation is unauthenticated (no auth headers required); alert on POST requests to /Servlet/Skins from unauthenticated sessions containing multipart file uploads with .jsp filenames.
  • The vulnerability is classified as CWE-22 (Path Traversal); the 'guid' parameter is the traversal vector in the /Servlet/Skins endpoint.
  • ·The nuclei template uses a random string ({{randstr}}) for the uploaded JSP filename, meaning the exact filename will vary per exploitation attempt; detection should focus on the pattern of .jsp file uploads via /Servlet/Skins rather than a static filename.
  • ·The template requires 2 HTTP requests (upload + trigger); both the POST to /Servlet/Skins and the subsequent GET to the dropped JSP are needed for full exploitation confirmation.

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv3.08.8HIGHCVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
vulncheck9.8CRITICAL
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