CVE-2026-69659 Memory exhaustion via unbounded deserialization of keyset pagination cursors in Ash.Page.Keyset
Attackers can cause denial of service by sending crafted keyset pagination cursors that trigger memory exhaustion via unsafe deserialization.
- 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-2026-69659?
CVE-2026-69659 is a medium-severity unsafe deserialization vulnerability in ash-project ash, published on 9 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Uncontrolled Resource Consumption vulnerability in ash-project ash allows an attacker to exhaust the memory of the node via a crafted keyset pagination cursor.
Read actions with keyset pagination deserialize the client-supplied page[:after] or page[:before] cursor in decode_values/2 in lib/ash/page/keyset.ex, which base64-decodes the value and passes it to :erlang.binary_to_term/2 without bounding its size. The Erlang external term format supports zlib-compressed payloads, which the decoder inflates transparently, so a cursor of a few kilobytes can allocate tens of megabytes of heap in a single call. Ash itself only ever encodes cursors uncompressed, so the decoder accepts a term shape its encoder never produces. Concurrent requests aggregate these allocations and can terminate the node.
This issue affects ash: from 1.17.0 before 3.31.1.
Weakness: CWE-502
Which versions are affected by CVE-2026-69659?
1 open source package ship an affected version, including ash. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
ash Hex | From 1.17.0 | 3.31.1 |
Products include Ash-Hq Ash Framework.
How do I fix CVE-2026-69659?
Upgrade ash to 3.31.1 or later.
Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.
Is CVE-2026-69659 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-69659 exists.
Other vulnerabilities in ash-project ash
Sources
Also known as EEF-CVE-2026-69659, GHSA-j35q-v8h8-7mwq.