redis-security

Redis Security

Production hardening for Redis: authentication, ACL-based access control, and network exposure. Cover all three together — any one of them on its own leaves an exploitable gap.

When to apply

• Deploying or reviewing a Redis instance destined for production.
• Setting up application credentials beyond a shared password.
• Auditing a Redis deployment against a security checklist.
• Receiving "Redis exposed to the internet" findings from a scanner.

1. Always authenticate (and use TLS)

Never run a production Redis without a password. Pair authentication with TLS so credentials and data aren't sent in clear text.

# redis.conf
requirepass your-strong-password
tls-port 6380
tls-cert-file /path/to/redis.crt
tls-key-file  /path/to/redis.key

r = redis.Redis(
    host="localhost",
    port=6380,
    password="your-strong-password",
    ssl=True,
    ssl_cert_reqs="required",
)

If you can use ACL users (next section) instead of the single requirepass, do — requirepass is effectively the legacy "default user" shortcut.

See references/auth.md.

2. ACLs for least-privilege access

The default user with a shared password is fine for development. For production, give each application a dedicated ACL user with only the commands and key patterns it actually needs.

# Cache-only reader
ACL SETUSER app_readonly on >password ~cache:* +get +mget +scan

# Writer that can't run dangerous ops
ACL SETUSER app_writer   on >password ~*        +@all -@dangerous

# Admin (use sparingly, never for application traffic)
ACL SETUSER admin        on >strong-password ~* +@all

Useful command categories:

Category	What it covers
@read	Read commands (GET, MGET, HGET, ...)
@write	Write commands (SET, DEL, XADD, ...)
@dangerous	FLUSHALL, DEBUG, KEYS, etc.
@admin	Administrative commands

If app credentials leak, a tight ACL bounds the blast radius — the attacker can't FLUSHALL your DB just because they grabbed a cache reader's password.

See references/acls.md.

3. Restrict network access

The most common Redis breach is a public-internet Redis with no auth. Avoid that with three layers:

# redis.conf — bind to specific interfaces, keep protected-mode on
bind 127.0.0.1 192.168.1.100
protected-mode yes

# Firewall — allow only application subnets
iptables -A INPUT -p tcp --dport 6379 -s 192.168.1.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 6379 -j DROP

Anti-pattern: bind 0.0.0.0 + protected-mode no — exposes Redis to the whole network without protection.

Optional but recommended: rename or disable destructive commands so a compromised client can't trash the DB:

rename-command FLUSHALL ""
rename-command DEBUG ""
rename-command CONFIG ""

See references/network.md.

References

• Redis: Security
• Redis: ACL