Severity by source
AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N
REST API exploitation is network-accessible (AV:N not AV:L); PR:L reflects required non-read-only authentication; S:C captures sub-CA trust propagating beyond Lemur to relying systems.
Primary rating from Vendor (github).
CVSS VectorVendor: github
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N
Lifecycle Timeline
3Blast Radius
ecosystem impact- 3 pypi packages depend on lemur (3 direct, 0 indirect)
Ecosystem-wide dependent count for version 1.9.3.
DescriptionCVE.org
Lemur manages TLS certificate creation. Prior to 1.9.3, POST /api/1/authorities with type=subca did not require AuthorityPermission on the parent authority when ADMIN_ONLY_AUTHORITY_CREATION was false. AssociatedAuthoritySchema resolved the caller-supplied parent and passed it through authority creation to cryptography-issuer, which used the parent authority_certificate.private_key to sign a new intermediate. Any authenticated non-read-only user in that supported configuration could chain a sub-CA to an internal root for which the user held no role. The resulting intermediate could issue trusted certificates and its private key could be used outside Lemur, bypassing normal issuance controls. The fix checks AuthorityPermission on every supplied parent before invoking the issuer. This issue is fixed in version 1.9.3.
AnalysisAI
Privilege escalation in Netflix Lemur's certificate authority API allows any authenticated non-read-only user to mint a sub-CA chained to an internal root CA they do not control, when the ADMIN_ONLY_AUTHORITY_CREATION flag is disabled. The POST /api/1/authorities endpoint (type=subca) failed to verify AuthorityPermission on the caller-supplied parent, allowing the caller to invoke cryptography-issuer which signed the new intermediate using the parent root's private key. …
Unlock full vulnerability intelligence
- Risk assessment & exploitation conditions
- Attack chain visualization
- Remediation with exact patch versions
- Threat intelligence from 22 sources
- Personal watchlist & email alerts
Free forever · No credit card required
Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | Exploitation requires three concurrent conditions: (1) the Lemur deployment must have ADMIN_ONLY_AUTHORITY_CREATION set to false - this is not the default configuration, making the population of vulnerable deployments a subset of all Lemur installations; (2) the attacker must hold a valid Lemur account that is not restricted to read-only access (PR:L per CVSS - any non-read-only authenticated user suffices, including self-service users); and (3) the targeted deployment must be running Lemur prior to version 1.9.3. … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | The provided CVSS vector (AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N, score 6.5) assigns a local attack vector, which conflicts with the vulnerability's mechanism - exploitation is a direct authenticated HTTP POST to a REST API endpoint, a network-accessible surface. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | An attacker with a valid non-admin Lemur account in a deployment running ADMIN_ONLY_AUTHORITY_CREATION=false sends a crafted POST /api/1/authorities request specifying type=subca and a parent authority ID corresponding to an internal root CA for which they hold no role. Lemur resolves the parent authority, invokes cryptography-issuer without checking permissions, and signs the new intermediate using the root's private key. … |
| Remediation | Upgrade Lemur to version 1.9.3 or later, available at https://github.com/Netflix/lemur/releases/tag/v1.9.3. … Detailed patch versions, workarounds, and compensating controls in full report. |
Threat intelligence, references, and detailed analysis are available after sign-in.
Same weakness CWE-862 – Missing Authorization
View allSame technique Authentication Bypass
View allShare
External POC / Exploit Code
Leaving vuln.today
EUVD-2026-61156
GHSA-g7p5-89mh-248h