CVE-2026-81319 Unsafe deserialization of decrypted terms enables node DoS in AshCloak
An attacker can crash the application by sending crafted encrypted data that triggers unsafe deserialization, causing resource exhaustion.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-81319?
CVE-2026-81319 is a medium-severity unsafe deserialization vulnerability in ash-project ash_cloak, published on 30 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Deserialization of Untrusted Data vulnerability in ash-project ash_cloak allows an attacker who can influence the bytes of an encrypted column to crash the BEAM node, by triggering unbounded atom creation or a decompression bomb during decryption.
AshCloak.Calculations.Decrypt decodes the decrypted binary with Ash.Helpers.non_executable_binary_to_term/1 without the :safe option, so atoms in the payload are interned during the decode and never garbage collected, and the term format's compressed form is inflated transparently. vault.decrypt!() is the only barrier and stops tampering only for an authenticated cipher. Cloak also ships the unauthenticated AES.CTR, whose ciphertext an attacker who knows their own plaintext can XOR into any same-length payload without the key, so an ordinary read of the forged column reaches the decoder. A few hundred kilobytes of distinct atoms exhausts the atom table, or a small compressed payload inflates to gigabytes.
This issue affects ash_cloak: from 0.1.0 before 0.4.0.
Weakness: CWE-502
Which versions are affected by CVE-2026-81319?
1 open source package ship an affected version, including ash_cloak.
| Package | Affected | Fixed in |
|---|---|---|
ash_cloak Hex | From 0.1.0 | 0.4.0 |
How do I fix CVE-2026-81319?
Upgrade ash_cloak to 0.4.0 or later.
Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.
Is CVE-2026-81319 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-81319 exists.
Sources
Also known as EEF-CVE-2026-81319, GHSA-rc26-mrm2-6pf9.