CVE-2026-31933 | Suricata stream: quadratic complexity in stream inspection

Suricata is a network IDS, IPS and NSM engine. Prior to versions 7.0.15 and 8.0.4, specially crafted traffic can cause Suricata to slow down, affecting performance in IDS mode. This issue has been patched in versions 7.0.15 and 8.0.4.

Published: 2026-04-02 Last update: 2026-04-07 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-31933 is rated Low Risk (31.7/100): CVSS High severity, with low exploitation likelihood (EPSS 0.02%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-31933

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-22 0.05% 0.02% -0.03%
2 2026-04-08 0.04% 0.05% +0.01%
3 2026-04-03 — 0.04% —

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-31933

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2026-31933

OS Trackers for CVE-2026-31933

vendor priority summary link
alpine — CVE-2026-31933: 1 source package rows (suricata); 11 state rows across 2 repos (3.23-community, edge-community); fixed 0, open 11. https://security.alpinelinux.org/vuln/CVE-2026-31933
debian not yet assigned CVE-2026-31933 not yet assigned priority: Debian including 1 source packages (suricata), 4 status rows across 4 suites (bullseye, forky, sid, trixie): resolved 3, open 1. https://security-tracker.debian.org/tracker/CVE-2026-31933
redhat high — https://access.redhat.com/security/cve/CVE-2026-31933
ubuntu medium CVE-2026-31933 medium priority: Ubuntu including 1 source packages (suricata), 6 status rows across 6 suites (bionic, jammy, noble, questing, upstream, xenial): needs-triage 6. https://ubuntu.com/security/CVE-2026-31933

Affected software / configurations for CVE-2026-31933

Vendor Product Version Raw CPE
oisf suricata < 7.0.15 cpe:2.3:a:oisf:suricata:*:*:*:*:*:*:*:*
oisf suricata >= 8.0.0, < 8.0.4 cpe:2.3:a:oisf:suricata:*:*:*:*:*:*:*:*

References for CVE-2026-31933

cvelogic Threat Intelligence