Suricata dhcp: unbounded transactions in unidirectional traffic can lead to resource exhaustion
Published Sep 18, 2026 · Updated Nov 3, 2026
Original summary
Normalized public record · Updated Nov 3, 2026
Suricata dhcp: unbounded transactions in unidirectional traffic can lead to resource exhaustion
Publisher and source text is retained separately from QFinch interpretation.
QFinch assessment
Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. From 8.0.0 until 8.0.6, the DHCP parser in rust/src/dhcp/dhcp.rs creates stateless transactions without recording their packet direction with AppLayerTxData::for_direction(), so a sensor that observes only one direction cannot mark the unseen direction inspected or free completed transactions. The RDP parser in rust/src/rdp/rdp.rs has the same direction-state defect. The per-flow transaction list can grow without bound and cleanup repeatedly scans it, causing increasing CPU and memory consumption and eventual denial of service. This issue is fixed in version 8.0.6.
Evidence: public source recordsAffected products
| Affected package, product or range | Fix status |
|---|---|
| Consult the referenced vendor advisory for affected versions. | Consult source advisory |
Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.
Remediation
Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.
- Confirm the affected product and reachable code path exist in your environment.
- Apply the vendor-supported patch or mitigation from the primary advisory.
- Rescan the exact deployed revision and retain verification evidence.
Evidence coverage
- SSVC priority
- LOW
- Confidence
- Not available
- Aliases
- None reported
Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.
Sources and record history
- Security advisory ↗
- Source repository ↗
- Patch commit ↗
- Patch commit ↗
- Patch commit ↗
- Patch commit ↗
- Source repository ↗
- https://redmine.openinfosecfoundation.org/issues/8621 ↗
Record history
Published Sep 18, 2026 · Last refreshed Nov 3, 2026