Cyber Resilience

CVE-2026-31933

DoS in Oisf Suricata ≤ 7.0.15

Published
02 April 2026
Modified
07 April 2026
Patch / advisory
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0035 28th percentile
Risk Priority 57 floored blend · peak EPSS

Summary

CVE-2026-31933 is a high-severity Inefficient Algorithmic Complexity (CWE-407) vulnerability in Oisf Suricata. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Endpoint Denial of Service (T1499); ranked at the 28th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SC-5 (Denial-of-service Protection) and SC-6 (Resource Availability) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2026-31933 is a denial-of-service vulnerability in Suricata, an open-source network intrusion detection system (IDS), intrusion prevention system (IPS), and network security monitoring (NSM) engine. Affecting versions prior to 7.0.15 and 8.0.4, the flaw (classified under CWE-407: Inefficient Algorithmic Complexity) allows specially crafted network traffic to trigger significant performance degradation, particularly in IDS mode. The issue stems from inefficient processing that leads to slowdowns, as scored at CVSS 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H), emphasizing high availability impact without compromising confidentiality or integrity.

Attackers require only network access to the monitored traffic, with no privileges, user interaction, or special complexity needed. By sending tailored packets to interfaces Suricata is inspecting, remote unauthenticated actors can cause the engine to consume excessive resources, resulting in slowed detection and monitoring capabilities. This effectively enables a denial-of-service condition targeted at the security tool itself, potentially blinding defenders during an attack.

Official advisories recommend upgrading to Suricata 7.0.15 or 8.0.4, where the issue has been patched. Details are available in the GitHub Security Advisory (GHSA-hvp5-gpr6-j4gp) and OISF Redmine issue 8272, which outline the fix and affected code paths.

EU & UK References

Vulnerability Data

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.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1499 Endpoint Denial of Service Impact
Adversaries may perform Endpoint Denial of Service (DoS) attacks to degrade or block the availability of services to users.
T1499.003 Application Exhaustion Flood Impact
Adversaries may target resource intensive features of applications to cause a denial of service (DoS), denying availability to those applications.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-31937Same product: Oisf Suricata
CVE-2026-31932Same product: Oisf Suricata
CVE-2026-31934Same product: Oisf Suricata
CVE-2025-29918Same product: Oisf Suricata
CVE-2026-22261Same product: Oisf Suricata
CVE-2026-22263Same product: Oisf Suricata
CVE-2024-55605Same product: Oisf Suricata
CVE-2024-45795Same product: Oisf Suricata
CVE-2024-47522Same product: Oisf Suricata
CVE-2024-55628Same product: Oisf Suricata

Affected Assets

oisf
suricata
≤ 7.0.15 · 8.0.0 — 8.0.4

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V1.2.9

Mitigating Controls (NIST 800-53 r5) AI

Denial-of-service protection directly reduces the impact of resource exhaustion triggered by worst-case algorithmic inputs.

Resource availability allocation limits blast radius when an inefficient algorithm is forced into its worst case.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices (code review, complexity analysis, safe algorithm selection) prevent introduction of exploitable worst-case behavior.

DE.CM-09 partial match
prevents

Runtime monitoring of software and resources can detect the performance impact of triggered worst-case complexity.

ID.RA-01 partial match
prevents

Identifying and recording algorithmic-complexity vulnerabilities directly addresses the root cause before exploitation.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

finds

Security testing can uncover performance issues stemming from algorithmic complexity.

mitigates

Redundancy of processing facilities can absorb resource exhaustion from inefficient algorithms.

finds

Monitoring activities can identify anomalous resource consumption indicative of algorithmic complexity attacks.

prevents

Secure development life cycle includes design reviews that can catch inefficient algorithms before deployment.

prevents

Secure system architecture principles encourage selection of algorithms with acceptable worst-case complexity.

prevents

Secure coding practices can include guidelines to avoid or mitigate inefficient algorithms.

References