CVE-2021-40539 is a critical authentication bypass vulnerability in Zoho ManageEngine ADSelfService Plus affecting builds up to 6113. The flaw resides in REST API URL handling, where improper URL normalization allows specially crafted requests to bypass the security filter that protects REST API endpoints. By reaching protected API functionality without valid authentication, a remote attacker can trigger follow-on actions that result in arbitrary command execution and remote code execution on the ADSelfService Plus server. Public reporting and vendor guidance indicate exploitation commonly led to deployment of web shells and subsequent compromise of the underlying Windows host and connected Active Directory environment.
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3 valid exploits after Mallory filtered fakes, detection scripts, and README-only repos (1 hidden).
This repository contains a single Metasploit module that exploits CVE-2021-40539, an authentication bypass vulnerability in the REST API of ManageEngine ADSelfService Plus. The exploit works by bypassing authentication, uploading a malicious Java JAR file to the server, and then executing it via a crafted API call. The module leverages Metasploit's payload generation capabilities, allowing the attacker to execute arbitrary code as the user running the ADSelfService Plus service (often SYSTEM on Windows). The main endpoints targeted are '/RestAPI/LogonCustomization' for both the authentication bypass and payload upload, and '/RestAPI/Connection' for payload execution. The exploit is weaponized, highly reliable, and leaves artifacts on disk and in logs. The repository is structured as a single Ruby file compatible with the Metasploit framework, and is intended for use by penetration testers and security researchers.
This repository contains a Python exploit script (exploit.py) targeting CVE-2021-40539, a critical authentication bypass and RCE vulnerability in ManageEngine ADSelfService Plus. The exploit works by uploading a JSP webshell and/or a malicious Java class to the vulnerable server via the '/./RestAPI/LogonCustomization' endpoint, then triggering remote code execution through the '/./RestAPI/Connection' endpoint. The script can optionally verify if the target is vulnerable before exploitation. If successful, the attacker gains a webshell at '/help/admin-guide/test.jsp', allowing arbitrary command execution. The repository is structured with a single exploit script and a README referencing external exploitation details. The exploit is operational, providing a working payload and automated exploitation steps.
This repository contains a Python exploit script (CVE-2021-40539.py) targeting Zoho ManageEngine ADSelfService Plus (version 6113 and earlier) for CVE-2021-40539, a critical authentication bypass and remote code execution vulnerability. The script allows both single-target and batch exploitation. It first checks if the target is vulnerable by sending a crafted POST request to the '/./RestAPI/LogonCustomization' endpoint. If vulnerable, it uploads a JSP webshell and a Java class file (either user-supplied or a default payload) to the same endpoint. The exploit then triggers RCE by sending a POST request to '/./RestAPI/Connection', leveraging the uploaded Java class. Finally, it verifies the webshell at '/help/admin-guide/test.jsp', which can be used to execute arbitrary commands on the target system. The repository also includes a README.md with usage instructions and background on the vulnerability. The exploit is operational, providing a working RCE chain with persistent access via the webshell.
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29 sources tracked across advisories, community write-ups, and news. New activity surfaces here as Mallory finds it.
An unpatched critical vulnerability in an authentication module that was exploited to gain access to servers hosting sensitive personal data in the ICRC/Red Cross breach.
A vulnerability (unspecified in the content) affecting Zoho ManageEngine ADSelfService that is listed as exploited by the threat actor UNC3886/Volt Typhoon.
A critical vulnerability in Zoho ManageEngine ADSelfService Plus referenced as being exploited in a cyberespionage campaign.
A critical authentication bypass vulnerability in ManageEngine ADSelfService Plus REST API URL handling that can lead to remote code execution via crafted URLs that bypass security filtering.
Query your assets running an affected version, and investigate the blast radius.
Every observed campaign linking this CVE to a named adversary.
Malware families riding this exploit, with evidence and IOCs.
YARA, Sigma, Snort, and vendor rules, auto-deployed to your SIEM.
Cross-references every affected SKU, including bundled OEM variants.
Community discussion across Reddit, Mastodon, and other social sources.