Medium · CVSS 5.9CVE-2026-82738

Ash.Type.UUIDv7 accepts non-v7 UUIDs that then fail to load, causing persistent denial of serviceCVE-2026-82738

Answer in brief

CVE-2026-82738 records a Medium severity (CVSS 5.9) vulnerability in Ash.Type.UUIDv7 accepts non-v7 UUIDs that then fail to load, causing persistent denial of service. The current sources do not mark it as known exploited. The current feed maps ash-project/ash (generic), ash-project/ash (generic), ash-project/ash-project/ash (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 1, 2026Updated Sep 1, 2026Source checked Oct 16, 2026First seen by HOL Sep 1, 2026Material review Sep 1, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 5.9
Exploitation: Not marked as known exploited
Affected software: 3 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 5.9. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps ash-project/ash (generic), ash-project/ash (generic), ash-project/ash-project/ash (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
ash-project/ashgeneric	>=751d8a4d11564efbe358c90c8347f3a00eb60782 <c453cdc0b8570e86ffef0d10e136247f52b3ea76	c453cdc0b8570e86ffef0d10e136247f52b3ea76
ash-project/ashgeneric	>=3.6.3 <3.32.2	3.32.2
ash-project/ash-project/ashgeneric	>=751d8a4d11564efbe358c90c8347f3a00eb60782 <c453cdc0b8570e86ffef0d10e136247f52b3ea76	c453cdc0b8570e86ffef0d10e136247f52b3ea76

Recommended response

Check inventory. Check lockfiles and deployed manifests for ash-project/ash, ash-project/ash, ash-project/ash-project/ash.
Review the reported fix. Update ash-project/ash to c453cdc0b8570e86ffef0d10e136247f52b3ea76; ash-project/ash to 3.32.2; ash-project/ash-project/ash to c453cdc0b8570e86ffef0d10e136247f52b3ea76 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 1, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 1, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 1, 2026

Sources and claim methodology

Upstream source description

Improper Input Validation vulnerability in ash-project ash allows an attacker to persistently deny reads of a record by storing a non-version-7 UUID in an Ash.Type.UUIDv7 attribute. Ash.Type.UUIDv7.cast_input/2 accepts any well-formed UUID string, including non-version-7 UUIDs, and stores it as a 16-byte binary. On read, cast_stored/2 (lib/ash/type/uuid_v7.ex) routes the stored binary back through cast_input/2, which since an input-validation tightening in v3.6.3 matches only version-7 (and optionally version-4) 16-byte binaries and otherwise expects a 36-character string. A stored non-v7 16-byte binary matches neither clause and returns :error, so every later read of that record fails. An attacker able to set such an attribute poisons the row permanently. The fix decodes any 16-byte stored binary directly in cast_stored/2. This issue affects ash: from 3.6.3 before 3.32.2.

Quoted source text, attributed separately from HOL analysis.