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No exploitation reported

CVE-2018-0233

No exploitation reported by the sources we read.

  • Published2018-04-19
  • WeaknessCWE-400

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

A vulnerability in the Secure Sockets Layer (SSL) packet reassembly functionality of the detection engine in Cisco Firepower System Software could allow an unauthenticated, remote attacker to cause the detection engine to consume excessive system memory on an affected device, which could cause a denial of service (DoS) condition. The vulnerability is due to the affected software improperly handling changes to SSL connection states. An attacker could exploit this vulnerability by sending crafted SSL connections through an affected device. A successful exploit could allow the attacker to cause the detection engine to consume excessive system memory on the affected device, which could cause a DoS condition. The device may need to be reloaded manually to recover from this condition. This vulnerability affects Cisco Firepower System Software Releases 6.0.0 and later, running on any of the following Cisco products: Adaptive Security Appliance (ASA) 5500-X Series Firewalls with FirePOWER Services, Adaptive Security Appliance (ASA) 5500-X Series Next-Generation Firewalls, Advanced Malware Protection (AMP) for Networks, 7000 Series Appliances, Advanced Malware Protection (AMP) for Networks, 8000 Series Appliances, Firepower 4100 Series Appliances, FirePOWER 7000 Series Appliances, FirePOWER 8000 Series Appliances, Firepower 9300 Series Security Appliances, Firepower Threat Defense for Integrated Services Routers (ISRs), Firepower Threat Defense Virtual for VMware, Industrial Security Appliance 3000, Sourcefire 3D System Appliances. Cisco Bug IDs: CSCve23031.

Timeline

dates in UTC
  1. 2018-04-1920:29CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC
Indicators tagged with this CVE, per day0 indicators over 7 days
Block these indicators
  • Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2018-0233?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2018-0233?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD
Cisco secure firewall management center
BranchAffectedFixed in
5.4= 5.4.0no fix published
6.0= 6.0.0no fix published
6.1= 6.1.0no fix published
6.2= 6.2.0no fix published
6.2= 6.2.1no fix published

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

Advisories and patches

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof-of-concept repositories
none listed
PoC-in-GitHub

Sources

  • CISA-ADPSSVC decisionnone2024-11-29
  • OpenCVESSVC decisionnone—
  • NVDCVSS 3.08.6read 2026-10-23
  • NVDCVSS 2.07.8read 2026-10-23
  • CNAweakness (CWE)CWE-400read 2026-10-23
  • NVDweakness (CWE)CWE-400read 2026-10-23
  • FIRST EPSSEPSS score2.4 %2026-10-23

Technical details

CVSS v3 Vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Published
2018-04-19
Last Modified
2026-06-17
NVD status
Modified

Frequently asked questions

What is CVE-2018-0233?

A vulnerability in the Secure Sockets Layer (SSL) packet reassembly functionality of the detection engine in Cisco Firepower System Software could allow an unauthenticated, remote attacker to cause the detection engine to consume excessive system memory on an affected device, which could cause a denial of service (DoS) condition. The vulnerability is due to the affected software improperly handling changes to SSL connection states. An attacker could exploit this vulnerability by sending crafted SSL connections through an affected device. A successful exploit could allow the attacker to cause the detection engine to consume excessive system memory on the affected device, which could cause a DoS condition. The device may need to be reloaded manually to recover from this condition. This vulnerability affects Cisco Firepower System Software Releases 6.0.0 and later, running on any of the following Cisco products: Adaptive Security Appliance (ASA) 5500-X Series Firewalls with FirePOWER Services, Adaptive Security Appliance (ASA) 5500-X Series Next-Generation Firewalls, Advanced Malware Protection (AMP) for Networks, 7000 Series Appliances, Advanced Malware Protection (AMP) for Networks, 8000 Series Appliances, Firepower 4100 Series Appliances, FirePOWER 7000 Series Appliances, FirePOWER 8000 Series Appliances, Firepower 9300 Series Security Appliances, Firepower Threat Defense for Integrated Services Routers (ISRs), Firepower Threat Defense Virtual for VMware, Industrial Security Appliance 3000, Sourcefire 3D System Appliances. Cisco Bug IDs: CSCve23031.

Is CVE-2018-0233 actively exploited?

Active exploitation of CVE-2018-0233 has not been confirmed. Its EPSS score was 2.4% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2018-0233?

CVE-2018-0233 has a CVSS v3 base score of 8.6 (HIGH severity), with vector string CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H.

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