Is CVE-2026-55736 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-55736 being exploited in the wild.

How severe is CVE-2026-55736?

Medium severity, with a CVSS score of 5.9, published 23 June 2026.

Is there a fix for CVE-2026-55736?

A patch was published on 2026-06-23: Fix committed to ash-project/ash repository Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-55736 attacked?

It is attacked with local access, in a software library.

Am I affected by CVE-2026-55736?

Check whether you run Erlang Ash at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-55736: Ash Framework private argument injection in Ash.Changeset

CVE-2026-55736 · Severity: medium · CVSS 5.9 · Published 2026-06-23

Ash is a framework for building Elixir applications. A security flaw was found where 'private' arguments—data intended to be set only by the server—can be manipulated by end-users. If an application uses these private arguments for critical tasks like verifying a user's identity or determining who owns a record, an attacker could potentially bypass security rules or modify data they shouldn't have access to.

Technologies: Erlang Ash. Vendors: Erlang.

Quick answers

Is CVE-2026-55736 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-55736 being exploited in the wild.
How severe is CVE-2026-55736?: Medium severity, with a CVSS score of 5.9, published 23 June 2026.
Which products and versions are affected?: Erlang Ash >= 3.0.0, < 3.29.3.
Is there a fix for CVE-2026-55736?: A patch was published on 2026-06-23: Fix committed to ash-project/ash repository Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-55736 attacked?: It is attacked with local access, in a software library.
Am I affected by CVE-2026-55736?: Check whether you run Erlang Ash at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A vulnerability exists in the Ash framework's changeset building process where private action arguments (defined with 'public?: false') are not consistently stripped from untrusted input. In the standard changeset path (for_create, for_update, for_destroy), the filtering logic fails when parameter keys are provided as strings (binaries) rather than atoms, which is the default for user-supplied data. Additionally, the atomic and bulk update paths (fully_atomic_changeset/4) fail to strip private arguments entirely. An attacker can exploit this to inject values into arguments intended for internal server-side use, such as 'acting_user_id', leading to privilege escalation or integrity violations. The issue is fixed in version 3.29.3.

Affected products

ash-project ash >= 3.0.0, < 3.29.3

Identifiers

CVE-2026-55736
GHSA-f4hc-ppw9-4hhw

Timeline

2026-06-23: advisory: Advisory published by GitHub and Erlang Ecosystem Foundation
2026-06-23: patched: Fix committed to ash-project/ash repository

References

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