Skip to main content
Threat Radar animated logo

CVE-2026-76489: Missing Release of Memory after Effective Lifetime in Cisco Cisco Open Source Snort3

0
Medium
VulnerabilityCVE-2026-76489cvecve-2026-76489
Published: 10/21/2026 (10/21/2026, 16:17:23 UTC)
Source: CVE Database V5
Vendor/Project: Cisco
Product: Cisco Open Source Snort3

Description

A memory management vulnerability in Cisco Open Source Snort3 allows an unauthenticated remote attacker to cause the Snort 3 Detection Engine to restart, resulting in a denial of service (DoS). The issue arises from incomplete error checking when processing files, leading to unreleased memory. Exploitation requires sending a large number of files to trigger the condition.

CVSS v3.1

Score 5.8medium

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Changed
Confidentiality
None
Integrity
None
Availability
Low
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L

Affected software

Cisco

Cisco Open Source Snort3

Affected versions
=3.12.2.0=3.1.2.0=3.1.3.0=3.1.4.0=3.1.5.0=3.1.6.0=3.1.7.0=3.1.8.0=3.1.9.0=3.1.10.0=3.1.12.0=3.1.13.0=3.1.14.0=3.1.15.0=3.1.16.0=3.1.17.0=3.1.18.0=3.1.19.0=3.1.20.0=3.1.21.0=3.1.22.0=3.1.23.0=3.1.24.0=3.1.25.0=3.1.27.0=3.1.28.0=3.1.29.0=3.1.30.0=3.1.31.0=3.1.32.0=3.1.36.0=3.1.38.0=3.1.39.0=3.1.40.0=3.1.41.0=3.1.42.0=3.1.43.0=3.1.45.0=3.1.47.0=3.1.48.0=3.1.50.0=3.1.51.0=3.1.52.0=3.1.53.0=3.1.55.0=3.1.56.0=3.1.57.0=3.1.58.0=3.1.59.0=3.1.60.0=3.1.61.0=3.1.62.0=3.1.63.0=3.1.64.0=3.1.65.0=3.1.66.0=3.1.67.0=3.1.69.0=3.1.70.0=3.1.71.0=3.1.72.0=3.1.73.0=3.1.74.0=3.1.75.0=3.1.76.0=3.1.77.0=3.1.78.0=3.1.81.0=3.1.82.0=3.1.83.0=3.1.84.0=3.2.1.0=3.2.2.0=3.3.0.0=3.3.1.0=3.3.2.0=3.3.3.0=3.3.4.0=3.3.5.0=3.3.7.0=3.5.0.0=3.5.1.0=3.8.1.0=3.6.0.0=3.6.2.0=3.9.3.0=3.7.2.0=3.7.0.0=3.9.6.0=3.10.0.0=3.10.2.0=3.7.4.0=3.9.0.0=3.5.2.0=3.12.1.0=3.6.1.0=3.9.2.0=3.6.3.0=3.9.5.0=3.7.1.0=3.9.7.0=3.7.3.0=3.10.1.0=3.9.1.0=3.11.1.0

Cisco

Cisco Secure Firewall Threat Defense (FTD) Software

Affected versions
=7.0.0=7.0.0.1=7.0.1=7.0.1.1=7.0.2=7.2.0=7.0.2.1=7.0.3=7.2.0.1=7.0.4=7.2.1=7.0.5=7.3.0=7.2.2=7.2.3=7.3.1=7.2.4=7.0.6=7.2.5=7.2.4.1=7.3.1.1=7.4.0=7.0.6.1=7.2.5.1=7.4.1=7.2.6=7.0.6.2=7.4.1.1=7.2.7=7.2.5.2=7.3.1.2=7.2.8=7.6.0=7.4.2=7.2.8.1=7.0.6.3=7.4.2.1=7.2.9=7.0.7=7.7.0=7.4.2.2=7.6.1=7.4.2.3=7.0.8=7.6.2=7.7.10=7.7.11=7.0.8.1=7.6.2.1=7.7.10.1=7.4.2.4=7.4.3=7.6.4=10.0.0=7.4.4=7.0.9=7.4.7

AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 10/21/2026, 16:46:03 UTC

Technical Analysis

CVE-2026-76489 affects multiple Cisco products using Snort 3 due to a flaw in memory management. Specifically, incomplete error checking during file processing can cause memory to remain unreleased. An attacker can exploit this by sending numerous files to Snort 3, causing the detection engine to restart unexpectedly and interrupt packet inspection. This results in a denial of service condition. The vulnerability has a CVSS 3.1 score of 5.8, indicating medium severity.

Potential Impact

Successful exploitation leads to the Snort 3 Detection Engine restarting, which interrupts packet inspection and causes a denial of service. There is no impact on confidentiality or integrity reported.

Mitigation Recommendations

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or patch links are provided in the available data. Until a patch is available, monitor vendor advisories for updates.

Pro Console: star threats, build custom feeds, automate alerts via Slack, email & webhooks.Upgrade to Pro

Technical Details

Data Version
5.2
Assigner Short Name
cisco
Date Reserved
2026-08-19T12:02:03.640Z
Cvss Version
3.1
State
PUBLISHED

Threat ID: 6ad8e8d64d27ba8daac3b6cc

Added to database: 10/21/2026, 16:31:18 UTC

Last enriched: 10/21/2026, 16:46:03 UTC

Last updated: 10/21/2026, 16:46:20 UTC

Views: 6

Community Reviews

0 reviews

Crowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.

Sort by
Loading community insights…

Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.

Actions

PRO

Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.

Please log in to the Console to use AI analysis features.

Need more coverage?

Upgrade to Pro Console for AI refresh and higher limits.

For incident response and remediation, OffSeq services can help resolve threats faster.

Latest Threats

Breach by OffSeqOFFSEQFRIENDS — 25% OFF

Check if your credentials are on the dark web

Instant breach scanning across billions of leaked records. Free tier available.

Scan now
OffSeq TrainingCredly Certified

Lead Pen Test Professional

Technical5-day eLearningPECB Accredited
View courses