CVE-2026-82740
LOW 2.1 PoC AVAILABLEImproper Input Validation vulnerability in ash-project ash fails to enforce the outer array constraints on a doubly-nested {:array, {:array, type}} attribute, letting invalid input pass validation. Ash.Type.apply_constraints/3 (lib/ash/type/type.ex) handled the {:array, {:array, type}} case by mapping only the inner {:array, type} constraints over each element, so constraints declared on the outer array (such as min_length, max_length, and nil_items?) were never applied. An attacker could submit an outer list that violates those constraints (too many elements, or nil entries where disallowed) and have it accepted and persisted. The fix enforces the outer array constraints and adds explicit handling for nil and non-list inputs. This issue affects ash: from 2.16.1 before 3.32.2.
Public exploit or PoC code exists. Modeled probability is still low, but the barrier to attack is reduced — watch closely.
Exploitation likelihood
0.1%chance of exploitation in 30 days · 3rd percentile
Impact if exploited
2.1CVSS 4.0 · LOW
- ConfidentialityNone
- IntegrityLow
- AvailabilityNone
What an attacker needs
- ⚠Access: Requires local access to the host
- ✓Privileges: No account or privileges required
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
- ⚠Requirements: Specific conditions must be present
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- reference https://github.com/ash-project/ash/security/advisories/GHSA-v29m-p28g-w5fc
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-82740/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-82740/poc.json
Weakness (CWE)
- CWE-20: Improper Input Validation
CVSS vector
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
All CVSS metrics
- LOW 2.1 v4.0 · CNA Primary
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - LOW 2.1 v4.0 · NVD Secondary
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X