CVE-2026-71855

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

Published: Sep 18, 2026Updated: Sep 23, 2026 Sources: CVE List NVDCWE-697

5.9MEDIUM

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:HAttack Complexity

High

PR:NPrivileges Required

None

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:HIntegrity

High

A:NAvailability

None

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Weaknesses

CWE-697

Affected Products

OISF

oss-projectaka suricata-update, libhtp, suricata

suricataOn-premNetwork Device

Networking Infrastructure / firewall

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

References

https://github.com/OISF/suricata/security/advisories/GHSA-fvwh-wjcq-2586

github.com

https://github.com/OISF/suricata/commit/181b3b2fdd1fe87e4534de4fc79e29a083ef125f

github.com

https://github.com/OISF/suricata/commit/4e2f23d031fbcfd72883bacd3d723c9874f23701

github.com

and 4 more references View all →

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