Security readout for executives and security teams
Plain-English summary
This flaw lets an unauthenticated outsider abuse a Quest KACE System Management Appliance installer download script to run commands on the appliance. Because CISA lists it in KEV, treat any exposed affected appliance as a serious compromise risk, not just a theoretical bug.
Executive priority
Immediate for any exposed Quest KACE SMA. The issue is unauthenticated remote command execution, rated CVSS 9.8, and listed by CISA as known exploited. Prioritize verification, remediation guidance, and compromise assessment.
Technical view
CVE-2018-11138 is CWE-78 command injection in /common/download_agent_installer.php on Quest KACE System Management Appliance 8.0.318. The source description says anonymous users can access the script and abuse it for arbitrary command execution. CVSS 3.1 is 9.8 with network, low complexity, no privileges, and no user interaction.
Likely exposure
Exposure is most likely where Quest KACE SMA 8.0.318 is deployed and the affected script is reachable by anonymous users, especially from untrusted networks. The bundle does not provide a complete affected-version matrix.
Exploitation context
Active exploitation is supported by CISA KEV. A public Exploit-DB reference is also listed, which increases practical risk, but this analysis does not rely on or reproduce exploit details.
Researcher notes
Evidence supports critical unauthenticated command execution in a named SMA script. The provided bundle identifies 8.0.318 but does not include a complete affected-version list or detailed patch instructions. Avoid assuming other versions or fixes without vendor confirmation.
Mitigation direction
- Inventory Quest KACE SMA appliances and confirm whether version 8.0.318 is present.
- Check Quest or Core Security guidance for version-specific fixes or mitigations.
- Remove direct internet exposure for KACE SMA management and installer endpoints.
- Restrict anonymous access paths where vendor guidance supports doing so.
- Prioritize incident review for any exposed affected appliance.
Validation and detection
- Confirm whether /common/download_agent_installer.php is anonymously reachable using approved safe checks.
- Review appliance, web, and proxy logs for suspicious anonymous access to the script.
- Verify the appliance version against vendor remediation guidance.
- Confirm compensating network controls block untrusted access to KACE SMA endpoints.
Public sources used
Michael Williams reviewed this cited source version on .
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-78: Command execution behavior lookup
Command injection weaknesses can lead defenders to review execution techniques and command interpreter telemetry. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2018-11138 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.8 (3.1)
- Known Exploited
- Yes
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CISA KEV status
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H3.95.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
9.8CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- 44950CVE reference · exploit, x_refsource_EXPLOIT-DB
- https://www.coresecurity.com/advisories/quest-kace-system-management-appliance-multiple-vulnerabilitiesCVE reference · x_refsource_MISC
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-11138CVE reference · government-resource
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.