CVE-2026-82737 Ash.Vector wraps the 16-bit dimension header for vectors over 65,535 elements, corrupting data and crashing reads
An attacker can cause denial of service and data corruption by submitting vectors with more than 65,535 elements, triggering an integer overflow in the Ash library.
- 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-2026-82737?
CVE-2026-82737 is a medium-severity vulnerability in ash-project ash, published on 1 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
Integer Overflow or Wraparound vulnerability in ash-project ash lets an attacker corrupt a stored vector and crash later reads of it by submitting a vector with more than 65,535 elements.
Ash.Vector.new/1 (lib/ash/vector.ex) encodes a vector as <<dim::unsigned-16, 0::unsigned-16>> followed by the element floats, packing the element count into a 16-bit field without checking its range. A list of more than 65,535 elements wraps the dimension modulo 65,536, so the encoded header records a dimension that disagrees with the number of stored floats. from_binary/1 later reads binary-size(dim)-unit(32) from the wrapped header, so every read of the corrupted value misparses and raises, denying access to the affected record. The fix rejects any vector whose dimension exceeds 65,535.
This issue affects ash: from 2.14.13 before 3.32.2.
Weakness: CWE-190
Which versions are affected by CVE-2026-82737?
1 open source package ship an affected version, including ash.
| Package | Affected | Fixed in |
|---|---|---|
ash Hex | From 2.14.13 | 3.32.2 |
How do I fix CVE-2026-82737?
Upgrade ash to 3.32.2 or later.
Is CVE-2026-82737 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-82737 exists.
Sources
Also known as EEF-CVE-2026-82737, GHSA-68q3-w4w3-2gfv.