CVE-2026-42809 — polaris-runtime-service
CVE-2026-42809 is a Improper Input Validation vulnerability in org.apache.polaris:polaris-runtime-service. A fix is available for org.apache.polaris:polaris-runtime-service — see the affected versions and patch details below.
Apache Polaris: staged table creation could vend storage credentials for unvalidated locations
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-42809.
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.
Real-World Exposure
org.apache.polaris:polaris-runtime-serviceReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
Apache Polaris can issue broad temporary ("vended") storage credentials during staged table creation before the effective table location has been validated or durably reserved. Those temporary credentials are meant to limit the scope of accessible table data and metadata, but this scope limitation becomes attacker- directed because the attacker can choose a reachable target location.
In the confirmed variant, if the caller supplies a custom location during
stage create and requests credential vending, Apache Polaris uses that location to
construct delegated storage credentials immediately. The stage-create path
itself neither runs the normal location validation nor the overlap checks
before those credentials are issued.
Closely related to that, the staged-create flow also accepts
write.data.path / write.metadata.path in the request properties and
feeds
those location overrides into the same effective table location set used for
credential vending. Those fields are secondary to the main custom-location
exploit, but they are still attacker-influenced location inputs that should
be
validated before any credentials are issued.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.apache.polaris:polaris-runtime-service | all versions | 1.4.1org.apache.polaris:polaris-runtime-service:1.4.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.polaris:polaris-runtime-service, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.apache.polaris:polaris-runtime-service to 1.4.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-42809 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-2026-42809 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-42809. 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-2026-42809 in your dependencies?
O3 Security finds CVE-2026-42809 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.