Deserialization of Untrusted Data vulnerability in ash-project ash allows an unauthenticated attacker to inject a filter expression through a forged keyset pagination cursor, resulting in SQL injection or code execution depending on the data layer.
Read actions with keyset pagination decode the client-supplied page[:after] or page[:before] cursor in decodevalues/2 in lib/ash/page/keyset.ex using nonexecutablebinarytoterm/2 with [:safe]. That guard blocks new atoms, funs, and ports, but not a struct built from atoms already interned in a running Ash application, so a decoded %Ash.Query.Call{} expression survives and is spliced into the keyset filter as a comparison value in dofilters/4 and evaluated. Because the cursor bypasses the Ash.Expr macro, the runtime never applies the private?/public? gate that would otherwise reject it. On AshPostgres the injected fragment is inlined into the SQL query; on the ETS and Simple data layers it is evaluated in-process as an arbitrary function call.
This issue affects ash: from 1.17.0 before 3.31.3.
{
"cwe_ids": [
"CWE-502",
"CWE-89"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/67xxx/CVE-2026-67579.json",
"cna_assigner": "EEF",
"unresolved_ranges": [
{
"extracted_events": [
{
"introduced": "f8fadc67e67c955bb68b3a8d642be13e2b7e8ca9"
},
{
"fixed": "91874dd5435bc0ffebd8a254acfa573b39b74520"
}
],
"source": "AFFECTED_FIELD"
}
]
}