Medium severity · published Sep 1, 2026
CVE-2026-82738
Ash.Type.UUIDv7 accepts non-v7 UUIDs that then fail to load, causing persistent denial of service
5.9
CVSS
0.2%
EPSS
No
On KEV
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.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 8% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AS
ash · ash-project
3.6.3 before 3.32.2; 751d8a4d11564efbe358c90c8347f3a00eb60782 before c453cdc0b8570e86ffef0d10e136247f52b3ea76 · source: vendor
Affected product
AS
ash
ash-project
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