CVE-2026-55166

Published: Ago 18, 2026 Last Modified: Ago 18, 2026
ExploitDB:
Other exploit source:
Google Dorks:
CRITICAL 9,9
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: low
User Interaction: none
Scope: changed
Confidentiality: high
Integrity: high
Availability: low

Description

AI Translation Available

Lemur manages TLS certificate creation. Prior to 1.9.2, authenticated users could influence an ACME authority acme_url without an effective server-side destination restriction and trigger AcmeHandler.setup_acme_client to make backend requests. An attacker could target cloud instance metadata or internal services from Lemur network context, potentially obtaining credentials available to the host. The advisory also identifies creator-equality authorization behavior that could preserve access to certificate key material after ownership or role changes, with insufficient export_private_key audit context to distinguish that access path. Together, the acme_url server-side request forgery and authorization weakness could expose cloud credentials and long-lived PKI private-key access. The fix adds ACME_DIRECTORY_HOST_ALLOWLIST validation and enriches key-export audit events with creator and current-owner context. This issue is fixed in version 1.9.2.

285

Improper Authorization

Draft
Abstraction: Class Structure: Simple
Common Consequences
Security Scopes Affected:
Confidentiality Integrity Access Control
Potential Impacts:
Read Application Data Read Files Or Directories Modify Application Data Modify Files Or Directories Gain Privileges Or Assume Identity Execute Unauthorized Code Or Commands
Applicable Platforms
Technologies: Not Technology-Specific, Web Server, Database Server
Likelihood of Exploit: High
View CWE Details
639

Authorization Bypass Through User-Controlled Key

Incomplete
Abstraction: Base Structure: Simple
Common Consequences
Security Scopes Affected:
Access Control
Potential Impacts:
Bypass Protection Mechanism Gain Privileges Or Assume Identity
Applicable Platforms
All platforms may be affected
Likelihood of Exploit: High
View CWE Details
918

Server-Side Request Forgery (SSRF)

Incomplete
Abstraction: Base Structure: Simple
Common Consequences
Security Scopes Affected:
Confidentiality Integrity Access Control
Potential Impacts:
Read Application Data Execute Unauthorized Code Or Commands Bypass Protection Mechanism
Applicable Platforms
Technologies: Web Based, AI/ML, Web Server
View CWE Details
https://github.com/Netflix/lemur/security/advisories/GHSA-v…
https://github.com/Netflix/lemur/security/advisories/GHSA-v2wp-frmc-5q3v
https://github.com/Netflix/lemur/commit/872f6e282542352f2bf…
https://github.com/Netflix/lemur/commit/872f6e282542352f2bf3f6e2bcc504ab81e1843d
https://github.com/Netflix/lemur/releases/tag/v1.9.2
https://github.com/Netflix/lemur/releases/tag/v1.9.2
https://github.com/Netflix/lemur/security/advisories/GHSA-v…
https://github.com/Netflix/lemur/security/advisories/GHSA-v2wp-frmc-5q3v