CVE-2018-18850

published 2018-10-31

CVE-2018-18850: In Octopus Deploy 2018.8.0 through 2018.9.x before 2018.9.1, an authenticated user with permission to modify deployment processes could upload a maliciously…

Priority P2 66 high 8.8 CVSS 3.0

AV N AC L PR L UI N S U C H I H A H

EXPLOIT

In Octopus Deploy 2018.8.0 through 2018.9.x before 2018.9.1, an authenticated user with permission to modify deployment processes could upload a maliciously crafted YAML configuration, potentially allowing for remote execution of arbitrary code, running in the same context as the Octopus Server (for self-hosted installations by default, SYSTEM).

Affected

2 ranges

Vendor	Product	Version range	Fixed in
octopus	octopus_server	2018.8.0 – 2018.8.12	—
octopus	octopus_server	>= 2018.9.0 < 2018.9.1	2018.9.1

Detection & IOCs extracted from sources · hover to see the quote

• → Look for authenticated uploads of YAML configuration files to Octopus Deploy deployment process endpoints, particularly from users with deployment process modification permissions. ↗
• → Monitor for PowerShell script steps being injected or executed on the Octopus Deploy server during a deployment, especially those originating from API key or credential-based authentication. ↗
• → Alert on processes spawned by the Octopus Server running as SYSTEM (self-hosted), particularly child processes of the Octopus service that are PowerShell instances. ↗
• → Exploitation can be performed using only valid credentials or an API key — monitor for API key usage triggering deployment process modifications followed by immediate deployment execution. ↗

• · Affected versions are specifically Octopus Deploy 2018.8.0 through 2018.9.x before 2018.9.1; detections should be scoped to this version range to reduce false positives. ↗
• · The exploit requires an authenticated session (valid credentials or API key); unauthenticated traffic to Octopus Deploy is not a vector for this CVE. ↗

CVSS provenance

nvd v3.0 8.8 HIGH CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

nvd v2.0 9.0 CRITICAL AV:N/AC:L/Au:S/C:C/I:C/A:C

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