CVE-2015-7546 — keystone
HIGHCVE-2015-7546 is a high-severity (CVSS 7.5) CWE-522 vulnerability in keystone. A fix is available for keystone — see the affected versions and patch details below.
OpenStack Identity Keystone and keystonemiddleware Insufficiently Protected Credentials
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-2015-7546 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 376,715 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
keystone🐍keystonemiddleware🐍keystone🐍keystonemiddleware🐍keystonemiddlewareReal-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
The identity service in OpenStack Identity (Keystone) before 2015.1.3 (Kilo) and 8.0.x before 8.0.2 (Liberty) and keystonemiddleware (formerly python-keystoneclient) before 1.5.4 (Kilo) and Liberty before 2.3.3 does not properly invalidate authorization tokens when using the PKI or PKIZ token providers, which allows remote authenticated users to bypass intended access restrictions and gain access to cloud resources by manipulating byte fields within a revoked token.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | keystone | ≥ 9.0.0.0b1&&< 9.0.0.0b2 | 9.0.0.0b2pip install --upgrade 'keystone==9.0.0.0b2' |
| 🐍PyPI | keystonemiddleware | ≥ 2.4.0&&< 4.1.0 | 4.1.0pip install --upgrade 'keystonemiddleware==4.1.0' |
| 🐍PyPI | keystone | ≥ 8.0&&< 8.1.0 | 8.1.0pip install --upgrade 'keystone==8.1.0' |
| 🐍PyPI | keystonemiddleware | all versions | 1.5.4pip install --upgrade 'keystonemiddleware==1.5.4' |
| 🐍PyPI | keystonemiddleware | ≥ 1.6.0&&< 2.3.3 | 2.3.3pip install --upgrade 'keystonemiddleware==2.3.3' |
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.
Fix
Update keystone to 9.0.0.0b2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2015-7546 is resolved across your whole dependency graph.
Workarounds
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-2015-7546 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2015-7546. 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-2015-7546 in your dependencies?
O3 Security finds CVE-2015-7546 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.