CVE-2026-82737: Ash.Vector wraps the 16-bit dimension header for vectors over 65,535 elements, corrupting data and crashing reads
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. frombinary/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.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
ash-project ashto a version that resolves this vulnerability.Fixed in 3.32.2 - Configuration
Update Ash.Vector.new/1 (lib/ash/vector.ex) to reject any vector whose dimension (element count) exceeds 65,535 so the 16-bit unsigned dimension header cannot wrap.
Ash.Vector (lib/ash/vector.ex) vector dimension range validation = reject dimensions > 65,535 - Operational
After upgrading, locate any stored vectors created with more than 65,535 elements and remove/correct them, since later reads will misparse the wrapped 16-bit dimension header and raise errors/deny access to affected records.