CVE-2026-93477

Description

Improperly Controlled Modification of Dynamically-Determined Object Attributes vulnerability in ash-project ash allows a user to set the value of a private action argument on the bulk destroy and bulk update paths. Action arguments declared with public?: false are meant to be set only by trusted server-side code (for example via Ash.Changeset.set_private_argument/3) and must not be settable from end-user input. CVE-2026-55736 fixed the non-bulk changeset path to strip private arguments from user-supplied parameter maps, but the bulk destroy and bulk update paths were not covered. Ash.Actions.Destroy.Bulk.base_changeset/5 and Ash.Actions.Update.Bulk.base_changeset/5 match every key in the caller-supplied parameter map against all of the action's arguments with no public? check, then apply the matches to the base changeset. A caller who can submit parameters to a bulk destroy or bulk update action (for example through AshJsonApi, AshGraphql, or a controller that forwards request parameters to Ash.bulk_destroy/4 or Ash.bulk_update/4) can therefore set any private argument of that action, including one referenced by an arg(...) template in the action's changes or validations. Depending on how the application uses the argument (for example an acting_user_id driving authorization or record ownership, or audit metadata), this can lead to an integrity violation or privilege escalation. The fix requires public? in the argument matching on both bulk paths; private arguments remain settable server-side via the :private_arguments option. This issue affects ash: from 2.17.15 before 3.33.11.

Is your site exposed to CVE-2026-93477?

Run a free security scan — no signup, results in seconds.

EPSS — Exploit Prediction

0.0020

Probability of exploitation

0.08%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-915 CWE-915

References

Other References

https://cna.erlef.org/cves/CVE-2026-93477.html https://github.com/ash-project/ash/commit/6b7ac53a0a2532291eb940d7beaf0fbb2da6fc4f https://github.com/ash-project/ash/commit/8c17434803b2e91de522bdfbd0ca918e5d5898df https://github.com/ash-project/ash/security/advisories/GHSA-c2p4-p7q6-hr2j https://osv.dev/vulnerability/EEF-CVE-2026-93477 https://github.com/ash-project/ash/security/advisories/GHSA-c2p4-p7q6-hr2j

Frequently Asked Questions

What is CVE-2026-93477? +

Improperly Controlled Modification of Dynamically-Determined Object Attributes vulnerability in ash-project ash allows a user to set the value of a private action argument on the bulk destroy and bulk update paths. Action arguments declared with public?: false are meant to be set only by trusted server-side code (for example via Ash.Changeset.set_private_argument/3) and must not be settable from end-user input. CVE-2026-55736 fixed the non-bulk changeset path to strip private arguments from user-supplied parameter maps, but the bulk destroy and bulk update paths were not covered. Ash.Actions.Destroy.Bulk.base_changeset/5 and Ash.Actions.Update.Bulk.base_changeset/5 match every key in the caller-supplied parameter map against all of the action's arguments with no public? check, then apply the matches to the base changeset. A caller who can submit parameters to a bulk destroy or bulk update action (for example through AshJsonApi, AshGraphql, or a controller that forwards request parameters to Ash.bulk_destroy/4 or Ash.bulk_update/4) can therefore set any private argument of that action, including one referenced by an arg(...) template in the action's changes or validations. Depending on how the application uses the argument (for example an acting_user_id driving authorization or record ownership, or audit metadata), this can lead to an integrity violation or privilege escalation. The fix requires public? in the argument matching on both bulk paths; private arguments remain settable server-side via the :private_arguments option. This issue affects ash: from 2.17.15 before 3.33.11.

How do I check if I'm vulnerable to CVE-2026-93477? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

Related Vulnerabilities

CVE-2025-24370

Django-Unicorn adds modern reactive component functionality to Django templates. Affected versions of Django-Unicorn are vulnerable to python class pollution vulnerability. …

CVE-2025-2304

A Privilege Escalation through a Mass Assignment exists in Camaleon CMS When a user wishes to change his password, the …

CVE-2025-58367

DeepDiff is a project focused on Deep Difference and search of any Python data. Versions 5.0.0 through 8.6.0 are vulnerable …

CVE-2025-9315

An unauthenticated device registration vulnerability, caused by Improperly Controlled Modification of Dynamically-Determined Object Attributes, has been identified in the MXsecurity …

CVE-2026-45058

electerm is an open-sourced terminal/ssh/sftp/telnet/serialport/RDP/VNC/Spice/ftp client. In 3.8.8 and earlier, there is persistent local-pty code execution via imported bookmarks or …

CVE-2026-46478

Flowise is a drag & drop user interface to build a customized large language model flow. Prior to version 3.1.2, …