CVE-2021-3563 — keystone
HIGHCVE-2021-3563 is a high-severity (CVSS 7.4) CWE-863 vulnerability in keystone. 3 public exploit references exist, so weaponization risk is real. No vendor fix is recorded yet; mitigation options are listed below.
Openstack Keystone Incorrect Authorization vulnerability
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2021-3563 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,333 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
keystoneReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
A flaw was found in openstack-keystone. Only the first 72 characters of an application secret are verified allowing attackers bypass some password complexity which administrators may be counting on. The highest threat from this vulnerability is to data confidentiality and integrity.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | keystone | all versions | No fix |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
A flaw was found in openstack-keystone. Only the first 72 characters of …
A flaw was found in openstack-keystone. Only the first 72 characters of …
A flaw was found in openstack-keystone. Only the first 72 characters of …
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for keystone, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Remediation status
No patched version of keystone has shipped for CVE-2021-3563 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2021-3563 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2021-3563. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2021-3563 in your dependencies?
O3 Security finds CVE-2021-3563 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.