CVE-2019-12300 — buildbot
CRITICALCVE-2019-12300 is a critical-severity (CVSS 9.8) Improper Authentication vulnerability in buildbot. A fix is available for buildbot — see the affected versions and patch details below.
Improper Authentication in Buildbot
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-2019-12300 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 377,238 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
buildbot🐍buildbotReal-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
Buildbot before 1.8.2 and 2.x before 2.3.1 accepts a user-submitted authorization token from OAuth and uses it to authenticate a user. If an attacker has a token allowing them to read the user details of a victim, they can login as the victim.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | buildbot | all versions | 1.8.2pip install --upgrade 'buildbot==1.8.2' |
| 🐍PyPI | buildbot | ≥ 2.0.0&&< 2.3.1 | 2.3.1pip install --upgrade 'buildbot==2.3.1' |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for buildbot, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update buildbot to 1.8.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2019-12300 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-2019-12300 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2019-12300. 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-2019-12300 in your dependencies?
O3 Security finds CVE-2019-12300 across PyPI dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.