{"id":86696,"date":"2026-03-15T21:20:15","date_gmt":"2026-03-15T21:20:15","guid":{"rendered":""},"modified":"-0001-11-30T00:00:00","modified_gmt":"-0001-11-30T00:00:00","slug":"cve-2025-8194-defect-in-cpython-tarfile-module-leading-to-system-compromise","status":"publish","type":"post","link":"https:\/\/www.ameeba.com\/blog\/cve-2025-8194-defect-in-cpython-tarfile-module-leading-to-system-compromise\/","title":{"rendered":"CVE-2025-8194: Defect in CPython “tarfile” Module Leading to System Compromise<\/strong>"},"content":{"rendered":"

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

The vulnerability CVE-2025-8194 pertains to a defect found in the \u201ctarfile\u201d module of CPython, affecting the \u201cTarFile\u201d extraction and entry enumeration APIs. This vulnerability can lead to a system deadlock, triggered by the incorrect handling of tar archives with negative offsets. This poses a significant risk to any system or application using the affected versions of CPython, potentially leading to unauthorized system access, data leakage, or even full system compromise.<\/p>\n

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

CVE ID: CVE-2025-8194
\nSeverity: High (7.5 CVSS Score)
\nAttack Vector: Network
\nPrivileges Required: None
\nUser Interaction: None
\nImpact: Potential system compromise or data leakage<\/p>\n

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

Product | Affected Versions<\/p>\n

CPython | All versions prior to patch<\/p>\n

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

The exploit takes advantage of a flaw in the tarfile module of CPython. When processing tar archives with negative offsets, the tar implementation enters an infinite loop, resulting in a deadlock. This can be leveraged by an attacker to craft a malicious tar archive that, when processed, would cause the system or application to hang indefinitely. This could potentially allow for further malicious activity, such as unauthorized system access or data leakage.<\/p>\n

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

Here’s a conceptual example of how the vulnerability might be exploited:<\/p>\n

import tarfile\ndef malicious_archive():\nwith tarfile.open(\"malicious.tar\", \"w\") as tar:\n# Create a tarinfo object with negative offset\ninfo = tarfile.TarInfo(name=\"malicious_file\")\ninfo.offset = -99999\n# Add the malicious tarinfo object to the tar archive\ntar.addfile(info)\n# Execute the function to create the malicious archive\nmalicious_archive()<\/code><\/pre>\n
This code creates a tar archive containing a file with a negative offset. When this archive is processed by the affected versions of CPython, it would trigger the infinite loop and deadlock.<\/p>\n","protected":false},"excerpt":{"rendered":"
Overview The vulnerability CVE-2025-8194 pertains to a defect found in the \u201ctarfile\u201d module of CPython, affecting the \u201cTarFile\u201d extraction and entry enumeration APIs. This vulnerability can lead to a system deadlock, triggered by the incorrect handling of tar archives with negative offsets. This poses a significant risk to any system or application using the affected […]<\/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":[],"tags":[],"vendor":[],"product":[],"attack_vector":[],"asset_type":[],"severity":[],"exploit_status":[],"class_list":["post-86696","post","type-post","status-publish","format-standard","hentry"],"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