{"description":"Trending threats, MITRE ATT\u0026CK coverage, and detection metadata. Fed continuously.","feed_url":"https://feed.craftedsignal.io/tags/detection-bypass/feed.json","home_page_url":"https://feed.craftedsignal.io/","items":[{"_cs_actors":[],"_cs_cpes":[],"_cs_cves":[{"cvss":8.1,"id":"CVE-2025-71343"}],"_cs_exploited":false,"_cs_has_poc":false,"_cs_poc_references":[],"_cs_products":["picklescan \u003c 0.0.30"],"_cs_severities":["high"],"_cs_tags":["deserialization","remote-code-execution","python","vulnerability","detection-bypass"],"_cs_type":"advisory","_cs_vendors":["picklescan"],"content_html":"\u003cp\u003eCVE-2025-71343 describes a critical vulnerability affecting \u003ccode\u003epicklescan\u003c/code\u003e versions prior to 0.0.30. This flaw stems from a detection bypass related to the \u003ccode\u003elib2to3.pgen2.pgen.ParserGenerator.make_label\u003c/code\u003e function within the \u003ccode\u003ereduce\u003c/code\u003e method, which is a key component in parsing Python bytecode. Attackers can leverage this vulnerability to craft highly sophisticated malicious pickle files. These files are specifically designed to contain embedded arbitrary commands but will successfully evade \u003ccode\u003epicklescan\u003c/code\u003e's security checks. When an application on a vulnerable system then uses the standard \u003ccode\u003epickle.load()\u003c/code\u003e function to deserialize one of these malicious files, the embedded commands are executed, resulting in arbitrary code execution. This poses a significant risk to systems that process untrusted pickle files, as the primary defense mechanism (\u003ccode\u003epicklescan\u003c/code\u003e) is rendered ineffective against this specific evasion technique.\u003c/p\u003e\n\u003ch2 id=\"attack-chain\"\u003eAttack Chain\u003c/h2\u003e\n\u003col\u003e\n\u003cli\u003eAttacker crafts a malicious Python pickle file containing arbitrary code, specifically exploiting the \u003ccode\u003elib2to3.pgen2.pgen.ParserGenerator.make_label\u003c/code\u003e function's \u003ccode\u003ereduce\u003c/code\u003e method to bypass \u003ccode\u003epicklescan\u003c/code\u003e's detection.\u003c/li\u003e\n\u003cli\u003eThe malicious pickle file is delivered to a target system, potentially through methods such as email attachments, malicious web downloads, or integration into a compromised software supply chain.\u003c/li\u003e\n\u003cli\u003eAn application or user on the target system processes or scans the received pickle file using \u003ccode\u003epicklescan\u003c/code\u003e version prior to 0.0.30.\u003c/li\u003e\n\u003cli\u003eDue to CVE-2025-71343, \u003ccode\u003epicklescan\u003c/code\u003e fails to identify the embedded malicious payload, incorrectly marking the file as benign.\u003c/li\u003e\n\u003cli\u003eA Python application or script on the target system subsequently loads the \u0026quot;undetected\u0026quot; malicious pickle file using \u003ccode\u003epickle.load()\u003c/code\u003e.\u003c/li\u003e\n\u003cli\u003eDuring the deserialization process, the embedded arbitrary code within the pickle file is executed in the context of the Python application.\u003c/li\u003e\n\u003cli\u003eThe attacker achieves arbitrary command execution on the compromised system, potentially leading to full system compromise, data exfiltration, or further lateral movement.\u003c/li\u003e\n\u003c/ol\u003e\n\u003ch2 id=\"impact\"\u003eImpact\u003c/h2\u003e\n\u003cp\u003eThe successful exploitation of CVE-2025-71343 allows an attacker to achieve arbitrary code execution on systems that process untrusted pickle files using vulnerable versions of \u003ccode\u003epicklescan\u003c/code\u003e. This can lead to complete system compromise, unauthorized access to sensitive data, installation of malware, or disruption of services. While no specific victim counts are provided, any organization or individual processing Python pickle files in environments where \u003ccode\u003epicklescan\u003c/code\u003e is used for security vetting (especially in data science, machine learning, or software development contexts) is at risk. The undetected nature of the attack makes it particularly dangerous, as security tools designed to prevent such threats are bypassed.\u003c/p\u003e\n\u003ch2 id=\"recommendation\"\u003eRecommendation\u003c/h2\u003e\n\u003cul\u003e\n\u003cli\u003eUpdate \u003ccode\u003epicklescan\u003c/code\u003e to version 0.0.30 or later immediately to patch CVE-2025-71343 and address the detection bypass vulnerability.\u003c/li\u003e\n\u003cli\u003eImplement strict controls on the ingestion and processing of untrusted pickle files, regardless of \u003ccode\u003epicklescan\u003c/code\u003e's output, especially from external or unverified sources.\u003c/li\u003e\n\u003cli\u003eEducate users and developers about the risks associated with deserializing untrusted data, specifically in the context of Python pickle files, to prevent arbitrary code execution (CWE-502).\u003c/li\u003e\n\u003c/ul\u003e\n","date_modified":"2026-07-04T02:19:30Z","date_published":"2026-07-04T02:19:30Z","id":"https://feed.craftedsignal.io/briefs/2026-07-picklescan-detection-bypass/","summary":"A deserialization vulnerability, CVE-2025-71343, in picklescan before version 0.0.30 allows attackers to craft malicious pickle files that evade detection and lead to arbitrary code execution when loaded via `pickle.load()`.","title":"CVE-2025-71343 — picklescan Detection Bypass via Malicious Pickle Files","url":"https://feed.craftedsignal.io/briefs/2026-07-picklescan-detection-bypass/"}],"language":"en","title":"CraftedSignal Threat Feed - Detection-Bypass","version":"https://jsonfeed.org/version/1.1"}