Introduction
Covermyass is a post-exploitation tool to cover your tracks on various operating systems. It was designed for penetration testing "covering tracks" phase, before exiting the compromised server. At any time, you can run the tool to find which log files exists on the system, then run again later to erase those files. The tool will tell you which file can be erased with the current user permissions. Files are overwritten repeatedly with random data, in order to make it harder for even very expensive hardware probing to recover the data.
It supports the three major operating systems (Linux, macOS, Windows) and a few smaller ones (FreeBSD, OpenBSD).
Current status
This tool is still in beta. Upcoming versions might bring breaking changes. For now, we're focusing Linux and Darwin support, Windows may come later.
Installation
Download the latest release :
curl -sSL https://github.com/sundowndev/covermyass/releases/latest/download/covermyass_linux_amd64 -o ./covermyass
chmod +x ./covermyass
Verify digital signatures
covermyass releases are signed using PGP key (rsa4096) with ID E5BC23488DA8C7AC
and fingerprint 1A662C679AD91F549A77CD96E5BC23488DA8C7AC
. Our key can be retrieved from common keyservers.
- Download binary, checksums and signature
curl -L https://github.com/sundowndev/covermyass/releases/latest/download/covermyass_linux_amd64 -o covermyass_linux_amd64 && \
curl -L https://github.com/sundowndev/covermyass/releases/latest/download/covermyass_SHA256SUMS -o covermyass_SHA256SUMS && \
curl -L https://github.com/sundowndev/covermyass/releases/latest/download/covermyass_SHA256SUMS.gpg -o covermyass_SHA256SUMS.gpg
- Import key
gpg --keyserver https://keys.openpgp.org --recv-keys 0xE5BC23488DA8C7AC
- Verify signature (optionally trust the key from gnupg to avoid any warning)
gpg --verify covermyass_SHA256SUMS.gpg covermyass_SHA256SUMS
- Verify checksum
sha256sum --ignore-missing -c covermyass_SHA256SUMS
Usage
$ covermyass -h
Usage:
covermyass [flags]
Examples:
Overwrite log files 5 times with a final overwrite with zeros to hide shredding
covermyass --write -z -n 5
Flags:
-f, --filter strings File paths to ignore (supports glob patterns)
-h, --help help for covermyass
-n, --iterations int Overwrite N times instead of the default (default 3)
-l, --list Show files in a simple list format. This will prevent any write operation
--no-read-only Exclude read-only files in the list. Must be used with --list
-v, --version version for covermyass
--write Erase found log files. This WILL shred the files!
-z, --zero Add a final overwrite with zeros to hide shredding
First, run an analysis. This will not erase anything.
$ covermyass
Loaded known log files for linux
Scanning file system...
Found the following files
/var/log/lastlog (29.5 kB, -rw-rw-r--)
/var/log/btmp (0 B, -rw-rw----)
/var/log/wtmp (0 B, -rw-rw-r--)
/var/log/faillog (3.2 kB, -rw-r--r--)
Summary
Found 4 files (4 read-write, 0 read-only) in 27ms
When you acknowledged the results, erase those files.
$ whoami
root
$ covermyass --write -n 100
Loaded known log files for linux
Scanning file system...
Found the following files
/var/log/lastlog (29.5 kB, -rw-rw-r--)
/var/log/btmp (0 B, -rw-rw----)
/var/log/wtmp (0 B, -rw-rw-r--)
/var/log/faillog (3.2 kB, -rw-r--r--)
Summary
Found 4 files (4 read-write, 0 read-only) in 27ms
⣾ Shredding files... (3.1 MB, 1.3 MB/s) [2s]
Successfully shredded 4 files 100 times
Filter out some paths :
$ covermyass -f '/foo/**/*.log' -f '/bar/foo.log'
License
Covermyass is licensed under the MIT license. Refer to LICENSE for more information.