CVE-2026-48593
Fix: oban-bg/oban_web@9998b7eCVE-2026-48593 is a Uncontrolled Resource Consumption vulnerability in oban_web. O3 Security confirms whether CVE-2026-48593 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Unbounded range expansion in cron describe causes memory exhaustion in oban_web
Exploitation Status
No confirmed exploitation observed yet
- 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-2026-48593.
Real-World Exposure
oban_webReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Hex packages — download data is not available via public APIs for these ecosystems.
Description
Uncontrolled Resource Consumption vulnerability in oban-bg oban_web ('Elixir.Oban.Web.CronExpr' modules) allows memory exhaustion via unbounded cron range expansion.
An attacker with access to schedule cron jobs can submit a malicious cron expression such as "0 0 1-100000000 * *". When a user with dashboard access views the cron job list, 'Elixir.Oban.Web.CronExpr':describe/1 is called to render the expression. parse_range/1 parses both range endpoints via Integer.parse/1 with no bounds check, and the downstream helpers expand_dom_parts/1 and expand_dow_parts/1 materialise the range eagerly via Enum.to_list/1, causing allocation of ~2.4 GB and stalling or crashing the BEAM node. A sibling helper extract_dom_values already validates range bounds, but the expansion helpers do not.
This issue affects oban_web: from 2.12.0 before 2.12.5.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 💧Hex | oban_web | ≥ 2.12.0&&< 2.12.5 | 2.12.5 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for oban_web. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update oban_web to 2.12.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-48593 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 pinpoints whether CVE-2026-48593 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-48593. 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-2026-48593 in your dependencies?
O3 detects CVE-2026-48593 across Hex dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.