Skip to main content

Suricata CVE-2026-31933

| EUVDEUVD-2026-18241 HIGH
Inefficient Algorithmic Complexity (CWE-407)
2026-04-02 security-advisories@github.com
7.5
CVSS 3.1 · Vendor: github
View

Attack ChainAIDerived

Hypothetical attack flow derived from CVE metadata – not a confirmed exploit chain

  1. Access
    Craft malicious network traffic
  2. Delivery
    Send to Suricata IDS engine
  3. Exploit
    Trigger inefficient parsing logic
  4. Execution
    Consume excessive CPU resources
  5. Impact
    Degrade IDS performance

Vulnerability Assessment

Weakness
CWE
ASVS 5.0
V2 - Validation and Business Logic Algorithmic complexity limits
Exploitation Conditions

Remote unauthenticated attacker sending specially crafted network traffic to Suricata 7.0.0-7.0.14 or 8.0.0-8.0.3 running in IDS mode. No victim interaction or special configuration required; default IDS deployments are vulnerable.

Impact

Real-world risk is MODERATE-HIGH with operational security implications. The CVSS 7.5 reflects accurate severity: network-accessible (AV:N), no authentication required (PR:N), low complexity (AC:L), and high availability impact (A:H). While not data-destructive, the availability impact is severe in context-degraded IDS performance creates detection gaps that attackers can exploit for lateral movement or data exfiltration. No confirmed active exploitation (no KEV listing) and no public exploit identified at time of analysis, reducing immediate urgency. However, the low attack complexity means adversaries with knowledge of Suricata deployments could easily weaponize crafted traffic patterns. Priority depends on deployment mode: CRITICAL for production IDS/IPS protecting sensitive networks where performance degradation equals security failure; MODERATE for test environments. The attack is automatable once traffic patterns are identified, and technical impact (creating monitoring blind spots) enables subsequent attacks.

Exploit ScenarioDerived

An external attacker identifies a target organization running vulnerable Suricata IDS monitoring critical network segments. The attacker crafts network traffic containing specific packet characteristics that trigger inefficient processing algorithms in Suricata's detection engine, causing CPU exhaustion and detection throughput degradation. With the IDS performance severely impacted and unable to process traffic in real-time, the attacker proceeds with secondary attacks (malware delivery, lateral movement, data exfiltration) knowing detection capabilities are compromised. The low attack complexity (AC:L) and no authentication requirement (PR:N) mean attackers can execute this remotely via normal network access without credentials or user interaction.

This Week Schedule remediation this week. Why: HIGH severity (CVSS 7.0-8.9).
Patch available 0.0% exploitation probability (EPSS)

Get an e-mail when this CVE is exploited, patched or re-scored. Free account.

Alert me

AnalysisAIv1 – Apr 02, 2026

Network-accessible resource exhaustion in Suricata IDS allows remote attackers to degrade detection performance via specially crafted traffic. Affects versions prior to 7.0.15 and 8.0.4 (CVSS 7.5 HIGH). Attack requires no authentication (PR:N) and low complexity (AC:L), enabling trivial performance degradation that could blind security monitoring. EPSS data not available, but no public exploit identified at time of analysis. Vendor patches released for both affected branches (7.0.15, 8.0.4).

RemediationAI

Vendor-released patches: Upgrade to Suricata version 7.0.15 for the 7.x branch or version 8.0.4 for the 8.x branch. These versions contain fixes for the algorithmic complexity issue causing performance degradation. Download patched releases from the official OISF Suricata repository or distribution-specific package managers. For SUSE Linux Enterprise environments (noted in tags), apply updates through SUSE security channels when available. No workarounds identified-patching is the primary mitigation strategy. Verify patch effectiveness by monitoring Suricata CPU utilization and packet processing rates under typical traffic loads post-upgrade. Consult the official security advisory at https://github.com/OISF/suricata/security/advisories/GHSA-hvp5-gpr6-j4gp and implementation details at https://redmine.openinfosecfoundation.org/issues/8272 for additional technical guidance.

Affected VersionsENISA

suricata 8.0.0, < 8.0.4
suricata < 7.0.15

Affected Packages

euvd suricata fix: 7.0.15, 8.0.4

Source: OSV (Open Source Vulnerabilities)

Affects your stack

Affects 1 package in euvd

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

Suricata is an open-source network threat detection engine performing intrusion detection (IDS), prevention (IPS), and network security monitoring. The vulnerability involves CWE-407 (Inefficient Algorithmic Complexity), where specially crafted network packets trigger computationally expensive processing paths within the detection engine. This algorithmic complexity issue causes CPU resource exhaustion during traffic analysis, degrading throughput and detection coverage. The flaw affects the core traffic inspection pipeline, making it exploitable via normal network attack surface without requiring direct access to the Suricata system itself. The issue is particularly critical for IDS deployments where performance degradation creates security blind spots by preventing timely threat detection.

Know when Suricata gets its next vulnerability

  • Watch products and get an email when something new is published
  • Check this CVE against your own stack and servers
  • Exploit and PoC references, threat intelligence from 22 sources

No credit card · 7-day full trial

Severity by source

Vendor (github) PRIMARY 7.5 HIGH
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Red Hat 7.5 HIGH

Primary rating from Vendor (github).

CVSS VectorVendor: github

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

Lifecycle Timeline

2
Patch released
Apr 02, 2026 - 20:30 nvd
Patch available
CVE Published
Apr 02, 2026 - 14:16 nvd
HIGH 7.5

DescriptionCVE.org

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.

Executive ViewAI

Why It Matters

CVE-2026-31933 affects Suricata IDS versions prior to 7.0.15 and 8.0.4, allowing unauthenticated remote attackers to degrade threat detection performance through resource exhaustion. This vulnerability directly undermines your organization's network monitoring and intrusion detection capabilities, potentially creating blind spots during active attacks when detection is most critical.

Business Impact: High
Compensating Controls

Vendor-released patch: Suricata 7.0.15 (7.x branch) and 8.0.4 (8.x branch). Until patched, implement network segmentation and rate-limiting on paths to IDS sensors; monitor Suricata CPU/memory metrics for anomalous spikes indicating potential resource exhaustion attacks. Consider temporary deployment of network-based DoS mitigation upstream of affected IDS systems.

Threat Intelligence Overview

EPSS Score
0.0%
Top 88% exploitable
Data Quality
8 sources
Confidence: High
EUVD NVD CVE.org EPSS Vulnrichment Vendor GitHub VulDB

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity HIGH
CISA KEV No
Public POC No
EPSS 0.0%
Patch available Yes
Active threat No
Deciding rule
HIGH severity (CVSS 7.0-8.9)
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision
Scheduled
Exploitation
None
System Exposure· derived
Open
Automatable
Yes
Human Impact
High
Technical Impact
Partial

Priority Score

38
Low Medium High Critical
KEV: 0
EPSS: 0
CVSS: +38
PoC: 0
Weaponized: 0
Threat intel: 0
Gov advisory: 0

Attack Technique

Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.

CVE-2025-12490 HIGH
8.8 Nov 06

Netgate pfSense CE Suricata Path Traversal Remote Code Execution Vulnerability. Rated high severity (CVSS 8.8), this vul

CVE-2018-1000167 HIGH POC
7.8 Apr 18

OISF suricata-update version 1.0.0a1 contains an Insecure Deserialization vulnerability in the insecure yaml.load-Functi

CVE-2025-59150 HIGH POC
7.5 Oct 01

Suricata is a network IDS, IPS and NSM engine developed by the OISF (Open Information Security Foundation) and the Suric

CVE-2021-45098 HIGH POC
7.5 Dec 16

An issue was discovered in Suricata before 6.0.4. Rated high severity (CVSS 7.5), this vulnerability is remotely exploit

CVE-2019-10056 HIGH POC
7.5 Aug 28

An issue was discovered in Suricata 4.1.3. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, n

CVE-2019-10055 HIGH POC
7.5 Aug 28

An issue was discovered in Suricata 4.1.3. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, n

CVE-2019-10054 HIGH POC
7.5 Aug 28

An issue was discovered in Suricata 4.1.3. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, n

CVE-2019-10052 HIGH POC
7.5 Aug 28

An issue was discovered in Suricata 4.1.3. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, n

CVE-2019-10051 HIGH POC
7.5 Aug 28

An issue was discovered in Suricata 4.1.3. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, n

CVE-2019-1010279 HIGH POC
7.5 Jul 18

Open Information Security Foundation Suricata prior to version 4.1.3 is affected by: Denial of Service - TCP/HTTP detect

CVE-2018-14568 HIGH POC
7.5 Jul 23

Suricata before 4.0.5 stops TCP stream inspection upon a TCP RST from a server. Rated high severity (CVSS 7.5), this vul

CVE-2015-8954 CRITICAL
9.8 Mar 20

The MemcmpLowercase function in Suricata before 2.0.6 improperly excludes the first byte from comparisons, which might a

Vendor StatusVendor

SUSE

Product Status
openSUSE Tumbleweed Fixed

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy