Reference page — cumulative record through Saturday, October 3, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-71855

CVE-2026-71855HIGH

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

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   L   N   N  U  N  H  N    7.5   .0031   21.5     —

AFFECTED
  Product   Versions             Fixed
  suricata  >= 8.0.0, < 8.0.6 –  —

TIMELINE
  Aug 7   Reserved by GitHub_M
  Sep 18  Published (CNA: GitHub_M)
  Sep 28  RESCORED — CVE-2026-71855 (OISF suricata). CVSS 5.9 → 7.5 (NVD).

CWE-697 · CNA: GitHub_M · CVSS v3.1 · 7 references · NVD status: Analyzed

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.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
August 7, 2026	Reserved	Reserved by GitHub_M
September 18, 2026	Published	Published (CNA: GitHub_M)
September 28, 2026	RESCORED	RESCORED — CVE-2026-71855 (OISF suricata). CVSS 5.9 → 7.5 (NVD).

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
OISF	suricata	—	>= 8.0.0, < 8.0.6	—

Weaknesses

CWE-697

References (7)

https://github.com/OISF/suricata/commit/181b3b2fdd1fe87e4534de4fc79e29a083ef125f [Patch]
https://github.com/OISF/suricata/commit/4e2f23d031fbcfd72883bacd3d723c9874f23701 [Patch]
https://github.com/OISF/suricata/commit/bc41dcc854e24487d3786ce578a8a86a8350ab20 [Patch]
https://github.com/OISF/suricata/releases/tag/suricata-7.0.17 [Release Notes]
https://github.com/OISF/suricata/releases/tag/suricata-8.0.6 [Release Notes]
https://github.com/OISF/suricata/security/advisories/GHSA-fvwh-wjcq-2586 [Vendor Advisory]
https://redmine.openinfosecfoundation.org/issues/8558 [Permissions Required]

Authoritative record: CVE-2026-71855 at cve.org

Vendors: oisf

Weaknesses: CWE-697

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-71855 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Saturday, October 3, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.