{"id":82114,"date":"2025-10-07T18:37:48","date_gmt":"2025-10-07T18:37:48","guid":{"rendered":""},"modified":"2025-11-02T11:12:38","modified_gmt":"2025-11-02T17:12:38","slug":"cve-2025-61622-remote-code-execution-vulnerability-in-python-s-pyfory-and-pyfury-libraries","status":"publish","type":"post","link":"https:\/\/www.ameeba.com\/blog\/cve-2025-61622-remote-code-execution-vulnerability-in-python-s-pyfory-and-pyfury-libraries\/","title":{"rendered":"CVE-2025-61622: Remote Code Execution Vulnerability in Python’s Pyfory and Pyfury Libraries<\/strong>"},"content":{"rendered":"

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

The vulnerability tracked as CVE-2025-61622 is a critical flaw that resides in the Pyfory library of Python, versions 0.12.0 through 0.12.2, and its predecessor Pyfury, versions from 0.1.0 through 0.10.3. This vulnerability, if exploited, could enable an attacker to execute arbitrary code on the affected system. It is of utmost importance due to its high severity<\/a> score and the potential for widespread impact, affecting any application that reads Pyfory serialized data from untrusted sources.<\/p>\n

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

CVE ID: CVE-2025-61622
\nSeverity: Critical (CVSS: 9.8)
\nAttack Vector: Network
\nPrivileges Required: None
\nUser Interaction: None
\nImpact: Potential system<\/a> compromise and data leakage<\/p>\n

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

Product | Affected Versions<\/p>\n

Python Pyfory | 0.12.0 – 0.12.2
\nPython Pyfury | 0.1.0 – 0.10.3<\/p>\n

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

The vulnerability stems from the deserialization<\/a> of untrusted data in Python’s Pyfory and Pyfury libraries. An attacker can craft a data stream that triggers the pickle-fallback serializer during deserialization<\/a>. The execution of `pickle.loads` is vulnerable to remote code<\/a> execution, allowing the attacker to run arbitrary code on the system.<\/p>\n

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

Here is a conceptual example of how an attacker could exploit this vulnerability. This pseudocode demonstrates the crafting of a malicious payload that triggers the pickle-fallback serializer:<\/p>\n

import pickle\nimport os\nclass Exploit(object):\ndef __reduce__(self):\nreturn (os.system, ('your malicious command here',))\nmalicious_payload = pickle.dumps(Exploit())<\/code><\/pre>\n
In this example, the `Exploit` class contains a `__reduce__` method that returns a tuple. The first element of the tuple is a callable (os.system), and the second is a tuple containing the arguments for the callable. When this object is unpickled, it will execute `os.system(‘your malicious command<\/a> here’)`.
\nThis payload could then be sent to an application using the vulnerable versions of the Pyfory or Pyfury libraries<\/a>. If the application deserializes the payload, it will trigger the execution of the malicious command<\/a>.<\/p>\n
Mitigation Guidance<\/strong><\/p>\n
Users are strongly recommended to upgrade to Pyfory version 0.12.3 or later, which has removed the pickle fallback serializer and thus fixes this issue. In cases where immediate patching is not possible, employing Web Application Firewalls (WAF) or Intrusion Detection Systems (IDS) could provide temporary mitigation. However, these should not be considered as long-term solutions, as they may not fully protect against exploits targeting this vulnerability<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"
Overview The vulnerability tracked as CVE-2025-61622 is a critical flaw that resides in the Pyfory library of Python, versions 0.12.0 through 0.12.2, and its predecessor Pyfury, versions from 0.1.0 through 0.10.3. This vulnerability, if exploited, could enable an attacker to execute arbitrary code on the affected system. It is of utmost importance due to its […]<\/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":[],"product":[],"attack_vector":[80],"asset_type":[],"severity":[],"exploit_status":[],"class_list":["post-82114","post","type-post","status-publish","format-standard","hentry","category-uncategorized","attack_vector-rce"],"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