CVE-2024-47188

What it actually does

Missing random seed initialization for the thash structure produces deterministic hash bucket assignments, enabling crafted inputs to collide into single buckets and trigger quadratic degradation in lookup and storage operations.

Why it matters to the business

Attackers can induce severe slowdowns in network traffic analysis, increasing the risk that malicious activity goes undetected and consuming disproportionate CPU and memory resources on monitoring systems.

How an attack unfolds

An attacker sends a stream of network packets whose headers are chosen to produce identical hash values under the known seed, concentrating all entries into one bucket and forcing repeated linear scans that exhaust performance.

How to fix it

Upgrade oisf/suricata to version 7.0.7 or later; apply commit 572a16fb5a28a582c6e219d946485d9778b64014 which initializes the random seed for thash before use.

How to confirm the fix worked

Confirm the running binary reports version 7.0.7 or newer; inspect source or binary for proper random seed initialization prior to thash table creation and run regression tests that measure bucket distribution under synthetic load.

Typical attack path

1. Map exposed Suricata instances via network reconnaissance
2. Generate packets engineered to collide under the fixed seed
3. Transmit high-volume colliding traffic toward the sensor
4. Sustain the flow until detection throughput collapses

How to detect it

Review Suricata performance and statistics logs for sudden drops in throughput or spikes in per-bucket occupancy; correlate with unusual traffic patterns that produce repeated hash values; no persistent artifacts remain after traffic ceases.

What your security team should do

• Apply the 7.0.7 update or the referenced commit across all deployments without delay
• Add Suricata version checks to automated inventory and patch pipelines
• Establish baseline performance metrics and alert on sustained deviations in packet processing rate