{"id":58376,"date":"2025-07-08T11:01:11","date_gmt":"2025-07-08T11:01:11","guid":{"rendered":""},"modified":"2025-08-09T12:55:05","modified_gmt":"2025-08-09T18:55:05","slug":"cve-2025-30379-release-of-invalid-pointer-in-microsoft-office-excel-leading-to-local-code-execution","status":"publish","type":"post","link":"https:\/\/www.ameeba.com\/blog\/cve-2025-30379-release-of-invalid-pointer-in-microsoft-office-excel-leading-to-local-code-execution\/","title":{"rendered":"CVE-2025-30379: Release of Invalid Pointer in Microsoft Office Excel Leading to Local Code Execution<\/strong>"},"content":{"rendered":"

Overview<\/strong><\/p>\n

The vulnerability under discussion, CVE-2025-30379, is a serious flaw found in Microsoft Office Excel that allows an unauthorized attacker to execute code locally. This vulnerability affects any user who utilizes Microsoft Office Excel, a widely used spreadsheet software. The severity of this vulnerability<\/a> is high, not only because of its potential for system compromise and data leakage, but also due to the ubiquitous use of the affected software, making a vast number of systems worldwide potential targets.<\/p>\n

Vulnerability Summary<\/strong><\/p>\n

CVE ID: CVE-2025-30379
\nSeverity: High (CVSS Score 7.8)
\nAttack Vector: Local
\nPrivileges Required: None
\nUser Interaction: Required
\nImpact: Potential system<\/a> compromise or data leakage<\/p>\n

Affected Products<\/strong><\/p>\n

Product | Affected Versions<\/p>\n

Microsoft Office<\/a> Excel | All versions prior to the patch<\/p>\n

How the Exploit Works<\/strong><\/p>\n

The vulnerability lies in the improper handling of memory<\/a> objects by Microsoft Office Excel. When a specially crafted Excel file is opened, it triggers the release of an invalid pointer or reference. This can lead to undefined behavior, such as memory corruption<\/a> or application crashes. However, a skilled attacker can manipulate this undefined behavior to execute arbitrary code<\/a> in the context of the current user.
\nIf the current user is logged in with administrative privileges<\/a>, the attacker can take control of the affected system. This could potentially lead to system<\/a> compromise, allowing the attacker to install programs, view, change, or delete data, or create new accounts with full user rights.<\/p>\n

Conceptual Example Code<\/strong><\/p>\n

In this conceptual example, an attacker might embed malicious code in an Excel file that triggers the vulnerability<\/a> when the file is opened. The code might look something like this:<\/p>\n

Sub Workbook_Open()\nDim buffer As String\nbuffer = Space(4096) ' Create a large string.\nRange(\"A1\").Value = buffer ' Release the invalid pointer.\nShell \"cmd.exe \/c \" & \"malicious_command\" ' Execute arbitrary code.\nEnd Sub<\/code><\/pre>\n
This VBA (Visual Basic for Applications) code creates a large string that triggers the memory corruption<\/a> when assigned to a cell (“A1”). The Shell function then executes arbitrary<\/a> command-line instructions within the context of the current user.
\nPlease note that this is a simplified and conceptual example. Actual exploits might involve more complex and obfuscated code.<\/p>\n","protected":false},"excerpt":{"rendered":"
Overview The vulnerability under discussion, CVE-2025-30379, is a serious flaw found in Microsoft Office Excel that allows an unauthorized attacker to execute code locally. This vulnerability affects any user who utilizes Microsoft Office Excel, a widely used spreadsheet software. The severity of this vulnerability is high, not only because of its potential for system compromise […]<\/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,"_monsterinsights_skip_tracking":false,"footnotes":""},"categories":[1],"tags":[],"vendor":[82],"product":[],"attack_vector":[],"asset_type":[],"severity":[],"exploit_status":[],"class_list":["post-58376","post","type-post","status-publish","format-standard","hentry","category-uncategorized","vendor-microsoft"],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t