---
id: CVE-2026-82752
title: >-
  Improper Validation of Specified Quantity in Input vulnerability in
  ash-project ash allows an attacker to store a value of arbitrary size in an
  attribute whose length constraint should bound it.


  Ash measures string length with Elixir's …
summary: >-
  Improper Validation of Specified Quantity in Input vulnerability in
  ash-project ash allows an attacker to store a value of arbitrary size in an
  attribute whose length constraint should bound it.


  Ash measures string length with Elixir's …
severity: medium
cvss: 5.9
cvssVector: 'CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N'
cwe:
  - CWE-1284
vendor: ash-project
product: ash
affected:
  - ash >= 0.10.0 < 3.33.0
  - ash-project/ash >= 05848d5f4affe60fddd812222a18ada080c0813b < *
published: '2026-09-05'
updated: '2026-09-08'
sourceUpdated: '2026-09-08T19:20:01.577'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-82752'
references:
  - url: 'https://cna.erlef.org/cves/CVE-2026-82752.html'
    label: 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
  - url: >-
      https://github.com/ash-project/ash/commit/a64cab49b8886503e6b7c7b211d83c475aac48ca
    label: 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
  - url: >-
      https://github.com/ash-project/ash/commit/cdbf4c4da6bda5f6f139078f01a64320b595216d
    label: 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
  - url: 'https://github.com/ash-project/ash/security/advisories/GHSA-cwjv-574p-59f6'
    label: 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
  - url: 'https://osv.dev/vulnerability/EEF-CVE-2026-82752'
    label: 6b3ad84c-e1a6-4bf7-a703-f496b71e49db
tags:
  - nvd
  - cve.org
  - exploit-available
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-08T18:19:23.967428Z'
cvssSource: cna
epss: 0.0018
epssPercentile: 0.06735
ingestedAt: '2026-09-06T10:53:51.733Z'
---

## Overview

Improper Validation of Specified Quantity in Input vulnerability in ash-project ash allows an attacker to store a value of arbitrary size in an attribute whose length constraint should bound it.

Ash measures string length with Elixir's String.length/1, which counts Unicode graphemes, in the max_length and min_length constraints of Ash.Type.String (apply_constraints/2 in lib/ash/type/string.ex), in Ash.Resource.Validation.StringLength, and in the string_length expression function. A grapheme carries an unbounded number of combining marks, so a base character followed by a million combining acute accents is one grapheme and megabytes of data, and satisfies max_length: 2. Where the data layer imposes no independent limit (ETS, Mnesia, or a Postgres text column) the whole value is persisted, so an attacker can write an entire request body into an attribute declared with a small maximum and grow storage without bound.

The counting unit also disagrees with the storage layer, which counts codepoints rather than graphemes, so a value accepted by the constraint can still be rejected or truncated by the column. A Postgres varchar(n) column bounds the value itself and is not exposed.

This issue affects ash: from 0.10.0 before 3.33.0.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.