CVE-2018-5440
No exploitation reported by the sources we read.
- Published2018-02-15
- Fixed in1.1.9.19
- WeaknessCWE-121 · CWE-787
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « 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 Stack-based Buffer Overflow issue was discovered in 3S-Smart CODESYS Web Server. Specifically: all Microsoft Windows (also WinCE) based CODESYS web servers running stand-alone Version 2.3, or as part of the CODESYS runtime system running prior to Version V1.1.9.19. A crafted request may cause a buffer overflow and could therefore execute arbitrary code on the web server or lead to a denial-of-service condition due to a crash in the web server.
Timeline
dates in UTC- 2018-02-1510:29CVE publishedNVD
Observed activity
isMalicious corpus · updated 2026-10-23 18:48 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2018-5440?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2018-5440?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 1.1 | < 1.1.9.19 | 1.1.9.19 | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 2.3 | = 2.3 | no fix published | NVD |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Distribution builds and vendor advisories
Packages from OSV.dev and products from the vendors' CSAF advisories.
version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.
Vendor advisories
3S-Smart Software Solutions GmbH CODESYS Web Server
CODESYS Web Server: Version 2.3 · CODESYS Web Server: prior to V1.1.9.19
Fix
- Update 3s-software codesys runtime system to 1.1.9.19
- Mitigation from the vendor CISA ICSA-18-032-02 · 2 productsThis vulnerability will be fixed by patch V.1.1.9.19 for the CODESYS V2.3 web server for Windows. This will be part of the CODESYS setup V2.3.9.56. The release of this security patch was made available on January 30, 2018.
- Mitigation from the vendor CISA ICSA-18-032-02 · 2 productsCurrently, 3S-Smart Software Solutions GmbH has not identified any workarounds for this vulnerability.
- Mitigation from the vendor CISA ICSA-18-032-02 · 2 productsUse controllers and devices only in a protected environment to minimize network exposure and ensure they are not accessible from outside.
- Mitigation from the vendor CISA ICSA-18-032-02 · 2 productsUse firewalls to protect and separate the control system network from other networks.
- Mitigation from the vendor CISA ICSA-18-032-02 · 2 productsUse VPN (Virtual Private Networks) tunnels if remote access is required.
- Mitigation from the vendor CISA ICSA-18-032-02 · 2 productsProtect both development and control systems from unauthorized access (e.g., by means of the operating system).
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
- NVDCVSS 3.19.8read 2026-10-23
- NVDCVSS 2.07.5read 2026-10-23
- CNAweakness (CWE)CWE-121read 2026-10-23
- NVDweakness (CWE)CWE-787read 2026-10-23
- FIRST EPSSEPSS score3.1 %2026-10-22
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Published
- 2018-02-15
- Last Modified
- 2026-06-17
- NVD status
- Modified
Frequently asked questions
What is CVE-2018-5440?
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What is the CVSS score for CVE-2018-5440?
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Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.