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CVE-2021-27905 is a critical server-side request forgery (SSRF) vulnerability in Apache Solr's ReplicationHandler, affecting all versions prior to 8.8.2. The flaw arises from insufficient validation of the 'masterUrl' (or 'leaderUrl') parameter, which is used to designate another ReplicationHandler for index data replication. Attackers can exploit this by sending crafted requests to the replication handler, causing the Solr server to make arbitrary HTTP requests to internal or external resources. The vulnerability is present only when Solr is configured in master-slave replication mode with the replication handler enabled.
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2 valid exploits after Mallory filtered fakes, detection scripts, and README-only repos (1 hidden).
This repository provides a proof-of-concept exploit for CVE-2021-27905, a Server-Side Request Forgery (SSRF) vulnerability in Apache Solr versions prior to 8.8.2. The repository contains four files: a detailed README.md explaining the vulnerability, exploitation steps, and mitigation; a Python exploit script (cve-2021-27905.py); a Docker Compose file for setting up a vulnerable Solr instance; and a requirements.txt for Python dependencies. The exploit script allows an attacker to force a vulnerable Solr server to make arbitrary HTTP requests by abusing the 'masterUrl' parameter of the replication handler. The script can automatically enumerate Solr cores or accept a user-supplied core name. The main attack vector is network-based SSRF, and the endpoints targeted are the Solr replication handler and core enumeration API. The exploit is a functional proof-of-concept and does not include weaponized payloads beyond SSRF. The repository is well-structured for both demonstration and testing in a local lab environment.
This repository contains a single Python exploit script (CVE-2021-27905.py) and a README. The script targets Apache Solr servers vulnerable to CVE-2021-27905, an SSRF (Server-Side Request Forgery) vulnerability. The exploit works by first enumerating available Solr cores via the /solr/admin/cores endpoint, then sending a replication fetchindex command with a masterUrl parameter pointing to an attacker-controlled DNS log domain. If the Solr server is vulnerable, it will make an outbound request to the supplied domain, which the attacker can observe to confirm SSRF. The script requires the user to supply the target Solr URL and a DNS log domain. The code is a proof-of-concept and does not provide a weaponized or post-exploitation payload. The repository is straightforward, with clear separation between the exploit code and usage instructions.
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