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macOS post-exploitation for credential harvesting, DTrace monitoring, TCC bypass, and stealth operations via native tools
Windows userland post-exploitation for credential harvesting, monitoring, AMSI/ETW bypass, and stealth operations
Kubernetes post-exploitation for container escape, secret extraction, RBAC abuse, and cluster persistence
Based on SOC occupation classification
Showing SKILL.md
| name | cis-ubuntu2004-v300-5-4-1-4 |
| description | Ensure strong password hashing algorithm is configured |
| category | cis-iam |
| version | 3.0.0 |
| author | cyberstrike-official |
| tags | ["cis","ubuntu","linux","ubuntu-20.04","users","authentication"] |
| cis_id | 5.4.1.4 |
| cis_benchmark | CIS Ubuntu Linux 20.04 LTS Benchmark v3.0.0 |
| tech_stack | ["ubuntu","linux"] |
| cwe_ids | [] |
| chains_with | [] |
| prerequisites | [] |
| severity_boost | {} |
A cryptographic hash function converts an arbitrary-length input into a fixed length output. Password hashing performs a one-way transformation of a password, turning the password into another string, called the hashed password.
ENCRYPT_METHOD (string) - This defines the system default encryption algorithm for encrypting passwords (if no algorithm are specified on the command line). It can take one of these values:
MD5 - MD5-based algorithm will be used for encrypting passwordSHA256 - SHA256-based algorithm will be used for encrypting passwordSHA512 - SHA512-based algorithm will be used for encrypting passwordBCRYPT - BCRYPT-based algorithm will be used for encrypting passwordYESCRYPT - YESCRYPT-based algorithm will be used for encrypting passwordDES - DES-based algorithm will be used for encrypting password (default)Note:
MD5_CRYPT_ENAB variable.The SHA-512 and yescrypt algorithms provide a stronger hash than other algorithms used by Linux for password hash generation. A stronger hash provides additional protection to the system by increasing the level of effort needed for an attacker to successfully determine local group passwords.
Run the following command to verify the hashing algorithm is sha512 or yescrypt in /etc/login.defs:
# grep -Pi -- '^\h*ENCRYPT_METHOD\h+(SHA512|yescrypt)\b' /etc/login.defs
Example output:
ENCRYPT_METHOD SHA512
- OR -
ENCRYPT_METHOD YESCRYPT
Output should show ENCRYPT_METHOD set to SHA512 or YESCRYPT.
Edit /etc/login.defs and set the ENCRYPT_METHOD to SHA512 or YESCRYPT:
ENCRYPT_METHOD <HASHING_ALGORITHM>
Example:
ENCRYPT_METHOD YESCRYPT
Note:
sha512 or yescrypt.sha512 or yescrypt, once it is changed, it is recommended that all group passwords be updated to use the stronger hashing algorithm./etc/login.defs and the PAM configurationENCRYPT_METHOD SHA512
v8 - 3.11 Encrypt Sensitive Data at Rest: Encrypt sensitive data at rest on servers, applications, and databases containing sensitive data. Storage-layer encryption, also known as server-side encryption, meets the minimum requirement of this Safeguard. Additional encryption methods may include application-layer encryption, also known as client-side encryption, where access to the data storage device(s) does not permit access to the plain-text data. (IG 2, IG 3)
v7 - 16.4 Encrypt or Hash all Authentication Credentials: Encrypt or hash with a salt all authentication credentials when stored. (IG 2, IG 3)
MITRE ATT&CK Mappings: T1003, T1003.008, T1110, T1110.002 - Tactics: TA0006 - Mitigations: M1041