Vulnerability in Oisf Suricata
CVE-2026-71855
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N.
EPSS exploit prediction
EPSS: 0.003 (23.8th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 24th percentile — 23.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000
Affected products
- Oisf Suricata — versions < 7.0.17, >= 8.0.0, < 8.0.6
Weakness classification (CWE)
References
- github.com/OISF/suricata/security/advisories/GHSA-fvwh-wjcq-2586 (Vendor Advisory)
- github.com/OISF/suricata/commit/181b3b2fdd1fe87e4534de4fc79e29a083ef125f (Patch)
- github.com/OISF/suricata/commit/4e2f23d031fbcfd72883bacd3d723c9874f23701 (Patch)
- github.com/OISF/suricata/commit/bc41dcc854e24487d3786ce578a8a86a8350ab20 (Patch)
- github.com/OISF/suricata/releases/tag/suricata-7.0.17 (Release Notes)
- github.com/OISF/suricata/releases/tag/suricata-8.0.6 (Release Notes)
- redmine.openinfosecfoundation.org/issues/8558 (Permissions Required)
Frequently asked questions
- What is CVE-2026-71855?
- CVE-2026-71855 is a medium-severity vulnerability in Oisf Suricata, classified under Incorrect Comparison. CVSS score: 5.9/10. Published 2026-09-18.
- How severe is CVE-2026-71855?
- Medium severity. CVSS v3 base score is 5.9 out of 10.