CVE-2026-108121

Status: DeferredMedium (6.9)—

Severity6.9Medium · CVSS 4.0

Exploitation probability0.31 %higher than 22% of CVEs

Active exploitationNonot in the CISA catalog

Public exploitNot knownno public code found

Brian Mariani from DigitalCanion SA has discovered a vulnerability in the domain creation functionality of koozali's SME Server version 11.0rc1-215, allowing an attacker with high privileges to inject reserved Apache configuration directives, corrupting httpd.conf and preventing Apache from starting after a server reboot, resulting in a denial-of-service (DoS) condition affecting the web server and its hosted virtual hosts.

CVSS

Base score: 6.9
Version: 4.0
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:N/VI:L/VA:H/SC:N/SI:L/SA:H/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:P/AU:Y/R:A/V:X/RE:M/U:Amber

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.31 %
Percentile among all scored CVEs: 22
Score date: 10/20/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1203 Exploitation for Client Executionexecution60 %
Primary impactT1499 Endpoint Denial of Serviceimpact55 %

Inferred by deterministic rules from the CVSS vector and CWE. Indicative only.

ATT&CK mitigations that cover these techniques

Filter Network Traffic Application Isolation and Sandboxing Exploit Protection Update Software

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Koozali — SME Server^AI

CWEs

CWE-20, CWE-96, CWE-400

References

Show 1 references

https://digitalcanion.com/en/security-research/#vendor=koozali

Raw JSON (NVD)

Show

{
  "id": "CVE-2026-108121",
  "cveTags": [],
  "metrics": {
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        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-108121",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-10-19T17:35:53.792314Z"
        }
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          "attackVector": "NETWORK",
          "baseSeverity": "MEDIUM",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:P/VC:N/VI:L/VA:H/SC:N/SI:L/SA:H/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:P/AU:Y/R:A/V:X/RE:M/U:Amber",
          "exploitMaturity": "PROOF_OF_CONCEPT",
          "providerUrgency": "AMBER",
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          "integrityRequirement": "NOT_DEFINED",
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          "availabilityRequirement": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "subConfidentialityImpact": "NONE",
          "vulnConfidentialityImpact": "NONE",
          "confidentialityRequirement": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "MODERATE",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED"
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  "affected": [
    {
      "source": "vulnerability@ncsc.ch",
      "affectedData": [
        {
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          "product": "SME Server",
          "versions": [
            {
              "status": "affected",
              "version": "11.0rc1-215"
            }
          ],
          "platforms": [
            "Linux"
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  "published": "2026-10-19T06:17:22.163",
  "references": [
    {
      "url": "https://digitalcanion.com/en/security-research/#vendor=koozali",
      "source": "vulnerability@ncsc.ch"
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  "vulnStatus": "Deferred",
  "weaknesses": [
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  "descriptions": [
    {
      "lang": "en",
      "value": "Brian Mariani from DigitalCanion SA has discovered a  vulnerability in the domain creation functionality of koozali's \nSME Server version 11.0rc1-215, allowing an attacker with high privileges \nto inject reserved Apache configuration directives, corrupting \nhttpd.conf and preventing Apache from starting after a server reboot, \nresulting in a denial-of-service (DoS) condition affecting the web \nserver and its hosted virtual hosts."
    }
  ],
  "lastModified": "2026-10-19T21:03:42.880",
  "sourceIdentifier": "vulnerability@ncsc.ch"
}