CVE-2026-82736

Description

Incorrect Behavior Order: Validate Before Canonicalize vulnerability in ash-project ash lets an attacker store a case-insensitive string value that violates its length or match constraints. Ash.Type.CiString.apply_constraints/2 (lib/ash/type/ci_string.ex) validated the max_length, min_length, and match constraints against the value as submitted, while the type case-folds the string (per its casing) for storage and comparison. Because validation ran before folding, an attacker can submit a value whose folded form breaks a constraint but whose original form passes: for example, against a match pattern requiring uppercase, an uppercase value that is stored lowercased persists a value the pattern rejects. The fix case-folds the value at the start of apply_constraints/2, so the constraints are checked against the form that is actually stored. This issue affects ash: from 1.29.0-rc0 before 3.32.2.

Predictions

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

References

• https://cna.erlef.org/cves/CVE-2026-82736.html
• https://github.com/ash-project/ash/commit/d8320b0127c8ef453679d70e5dd23a9506951d21
• https://github.com/ash-project/ash/security/advisories/GHSA-gg9w-7593-hxg9
• https://osv.dev/vulnerability/EEF-CVE-2026-82736

CWEs

CWE-180