CVE-2026-78038: Job argument injection via :args overrides primary_key and tenant in AshOban

Severity: medium (CVSS 5.9 v4.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-08-30 · updated 2026-09-01
Weakness: CWE-915

Description

Improperly Controlled Modification of Dynamically-Determined Object Attributes vulnerability in ash-project ash_oban allows a user whose input reaches the :args option of AshOban.build_trigger/3 to retarget an update or destroy trigger at another record, including across tenants. build_trigger/3 builds the trusted job arguments with atom keys (:primary_key, :tenant, :action_arguments) and merges the caller's :args underneath so the trusted values win on collision. Because Oban job arguments round-trip through JSON, the caller's keys arrive as strings, so Map.merge sees no collision and both keys survive. When the job is persisted the JSON object is de-duplicated keeping the last (string) key, and the worker reads the caller's value. The documentation describes :args as unable to affect the action, so an application that forwards user input into it for uniqueness scoping is exposed to authorization bypass and tenant isolation breaks. This issue affects ash_oban: from 0.2.5 before 0.8.14.

Affected products

ash-project ash_oban: from 0.2.5 before 0.8.14 — fixed in 0.8.14

How to fix

Upgrade to a fixed version: ash-project ash_oban 0.8.14. Check the vendor advisory for mitigations.

References

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