CVE-2026-71855

Suricata flow: IPv4/IPv6 hash collision can reuse wrong flow state

Published Sep 18, 2026 CVSS 3.1 · 5.9 Medium EPSS < 1% KEV · Not listed
Description
Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. Prior to 7.0.17 and 8.0.6, src/flow-hash.c can treat an IPv4 and IPv6 flow as equal without comparing the IP family when their raw address words, ports, protocol, VLAN, recursion level, live device, and hash bucket align. An IPv6 packet can therefore reuse IPv4 flow state or the reverse, causing incorrect flowbit state, detection bypass, or IP-only bypass. This issue is fixed in versions 8.0.6 and 7.0.17.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
CPEs cpe:2.3:a:oisf:suricata:*:*:*:*:*:*:*:*
Type Values Removed Values Added
First Time appeared Oisf
Oisf suricata
Vendors & Products Oisf
Oisf suricata
Type Values Removed Values Added
Description Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. Prior to 7.0.17 and 8.0.6, src/flow-hash.c can treat an IPv4 and IPv6 flow as equal without comparing the IP family when their raw address words, ports, protocol, VLAN, recursion level, live device, and hash bucket align. An IPv6 packet can therefore reuse IPv4 flow state or the reverse, causing incorrect flowbit state, detection bypass, or IP-only bypass. This issue is fixed in versions 8.0.6 and 7.0.17.
Title Suricata flow: IPv4/IPv6 hash collision can reuse wrong flow state
Weaknesses CWE-697
References
Metrics cvssV3_1

{'score': 5.9, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Sep 25, 2026, 7:22 PM
Reserved
Aug 7, 2026, 6:26 PM
Status
Analyzed
Published
Sep 18, 2026, 9:18 PM
Modified
Sep 28, 2026, 6:39 PM