CVE-2026-8469
Unauthenticated denial-of-service via BEAM atom table exhaustion in phoenix_storybook
Vulnerability description
Allocation of Resources Without Limits or Throttling vulnerability in phenixdigital phoenix_storybook allows unauthenticated denial-of-service via BEAM atom table exhaustion.
Multiple LiveView event handlers convert user-supplied event parameter strings to atoms using String.to_atom/1 without validation: 'Elixir.PhoenixStorybook.ExtraAssignsHelpers':handle_set_variation_assign/3 interns every key of the psb-assign params map; 'Elixir.PhoenixStorybook.ExtraAssignsHelpers':handle_toggle_variation_assign/3 interns the "attr" value from psb-toggle events; 'Elixir.PhoenixStorybook.ExtraAssignsHelpers':to_variation_id/2 interns elements of "variation_id"; and 'Elixir.PhoenixStorybook.ExtraAssignsHelpers':to_value/4 interns raw string values for attributes declared as :atom or :boolean. BEAM atoms are never garbage-collected, so each unique attacker-controlled string is a permanent allocation. Once the atom table ceiling (~1,048,576 atoms) is reached, the entire BEAM node aborts, taking down all applications running on it.
This issue affects phoenix_storybook from 0.2.0 before 1.1.0.
Affected
pkg:hex/phoenix_storybook
| Module | Source File | Routine |
|---|---|---|
Elixir.PhoenixStorybook.ExtraAssignsHelpers
|
lib/phoenix_storybook/helpers/extra_assigns_helpers.ex
|
PhoenixStorybook.ExtraAssignsHelpers.handle_set_variation_assign/3
|
Elixir.PhoenixStorybook.Story.Playground
|
lib/phx_live_storybook/live/entry_live.ex
|
PhoenixStorybook.ExtraAssignsHelpers.handle_toggle_variation_assign/3
|
PhoenixStorybook.ExtraAssignsHelpers.to_variation_id/2
|
||
PhoenixStorybook.ExtraAssignsHelpers.to_value/4
|
pkg:github/phenixdigital/phoenix_storybook
| Module | Source File | Routine |
|---|---|---|
Elixir.PhoenixStorybook.ExtraAssignsHelpers
|
lib/phoenix_storybook/helpers/extra_assigns_helpers.ex
|
PhoenixStorybook.ExtraAssignsHelpers.handle_set_variation_assign/3
|
Elixir.PhoenixStorybook.Story.Playground
|
lib/phx_live_storybook/live/entry_live.ex
|
PhoenixStorybook.ExtraAssignsHelpers.handle_toggle_variation_assign/3
|
PhoenixStorybook.ExtraAssignsHelpers.to_variation_id/2
|
||
PhoenixStorybook.ExtraAssignsHelpers.to_value/4
|
| Status | Type | Version | Changes / Fixed in |
|---|---|---|---|
| affected | git ⓘ | 0228669d55
|
< 96d524690a
|
Configurations
Phoenix Storybook must be mounted on a network-reachable route.
References
- https://github.com/phenixdigital/phoenix_storybook/security/advisories/GHSA-833p-95jq-929q vendor-advisory related
- https://osv.dev/vulnerability/EEF-CVE-2026-8469 related
- https://github.com/phenixdigital/phoenix_storybook/commit/96d524690af0fe197a49f60d18e564a620b9ef81 patch
Credits
- Finder: Peter Ullrich
- Remediation developer: Christian Blavier
- Analyst: Jonatan Männchen
CVE record as JSON:
GET /cves/CVE-2026-8469.json
OSV record as JSON:
GET /osv/EEF-CVE-2026-8469.json