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CVE-2020-26217 is an insecure deserialization vulnerability in XStream versions before 1.4.14. When XStream processes attacker-controlled XML using a blocklist-based security configuration, crafted serialized input can bypass the blocklist protections and invoke dangerous Java functionality, allowing arbitrary shell commands to be run. Deployments using XStream's Security Framework allowlist are not affected.
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2 valid exploits after Mallory filtered fakes, detection scripts, and README-only repos (2 hidden).
This repository contains a Go-based proof-of-concept exploit for CVE-2020-26217, a remote code execution vulnerability in the XStream Java library (versions <= 1.4.13). The exploit consists of a single Go file (CVE-2020-26217-poc.go) and a README.md with usage instructions and background information. The exploit works by constructing a malicious XML payload that leverages Java deserialization to execute arbitrary system commands on the target server. The payload is base64-encoded to bypass input filters and is sent as a GET parameter (e.g., ?data or ?xml) to a user-specified HTTP endpoint. The tool is interactive, allowing the user to input commands to be executed on the target. The README provides clear instructions and examples, including how to run the exploit and sample commands. No hardcoded endpoints are present; the user supplies the target URL. The exploit is operational, providing real command execution if the target is vulnerable.
This repository is a proof-of-concept exploit for CVE-2020-26217, a critical deserialization vulnerability in the XStream Java library (version 1.4.13). The structure includes a Maven project with a single Java entry point (Main.java) and an XML payload file (CVE-2020-26217.xml). The Java code uses XStream to deserialize the provided XML file, which is crafted to trigger a gadget chain resulting in arbitrary command execution (launching 'calc' on Windows). The exploit demonstrates the risk of deserializing untrusted XML with vulnerable XStream versions. No network endpoints are present; the attack vector is local file-based deserialization. The repository is well-structured for demonstration and educational purposes.
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4 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
XStream remote code execution through insecure XML deserialization when blocklists are relied upon.
A vulnerability referenced by the advisory without a technical description in the supplied content.
A remote-code-execution vulnerability in XStream caused by insecure XML deserialization when applications rely on blocklists.
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