{"id":"EEF-CVE-2026-77956","summary":"EEx template evaluation of prompt content in AshAi enables remote code execution","details":"## Summary\n\nImproper Control of Generation of Code (Code Injection) vulnerability in ash-project ash_ai allows a remote, unauthenticated client to execute arbitrary Elixir code.\n\n`AshAi.Actions.Prompt` evaluates prompt content through `EEx.eval_string/2`. The documented `prompt: fn input, context -\u003e ... end` form lets the prompt content be built from action arguments, so when a `prompt` action's text incorporates request data, that attacker-controlled text is compiled and run as an EEx template (Elixir source). Content such as `\u003c%= System.cmd(...) %\u003e` therefore executes on the server before any model request is made, requiring no authentication beyond reaching a prompt action. The fix stops evaluating function-supplied prompt content as EEx; only statically configured templates are evaluated.\n\nThis issue affects ash_ai: from 0.1.0 before 1.0.0.","aliases":["CVE-2026-77956","GHSA-2g59-hg7m-qc83"],"modified":"2026-09-08T03:45:06.382856399Z","published":"2026-08-31T00:56:26.440Z","database_specific":{"capec_ids":["CAPEC-242"],"cpe_ids":["cpe:2.3:a:ash-project:ash_ai:*:*:*:*:*:*:*:*"],"cwe_ids":["CWE-94"]},"references":[{"type":"ADVISORY","url":"https://github.com/ash-project/ash_ai/security/advisories/GHSA-2g59-hg7m-qc83"},{"type":"WEB","url":"https://cna.erlef.org/cves/CVE-2026-77956.html"},{"type":"FIX","url":"https://github.com/ash-project/ash_ai/commit/e9948254b5659c1143b73dc2f59f457931e64514"},{"type":"PACKAGE","url":"https://hex.pm/packages/ash_ai"}],"affected":[{"package":{"name":"ash_ai","ecosystem":"Hex","purl":"pkg:hex/ash_ai"},"ranges":[{"type":"SEMVER","events":[{"introduced":"0.1.0"},{"fixed":"1.0.0"}]}],"versions":["0.1.0","0.1.1","0.1.10","0.1.11","0.1.3","0.1.4","0.1.5","0.1.6","0.1.7","0.1.8","0.1.9","0.2.0","0.2.1","0.2.10","0.2.11","0.2.12","0.2.13","0.2.14","0.2.2","0.2.3","0.2.4","0.2.5","0.2.6","0.2.7","0.2.8","0.2.9","0.3.0","0.4.0","0.5.0","0.6.0","0.6.1","0.7.0","0.7.1","0.7.2","0.7.3","0.8.0","0.8.1","0.8.2"],"database_specific":{"source":"https://cna.erlef.org/osv/EEF-CVE-2026-77956.json"}},{"ranges":[{"type":"GIT","repo":"https://github.com/ash-project/ash_ai","events":[{"introduced":"4aab131d40a0bd5a8cf0b3c4eaaa59d49565f3d1"},{"fixed":"e9948254b5659c1143b73dc2f59f457931e64514"}]}],"versions":["v0.8.2","v0.8.1","v0.8.0","v0.7.3","v0.7.2","v0.7.1","v0.7.0","v0.6.1","v0.6.0","v0.5.0","v0.4.0","v0.3.0","v0.2.14","v0.2.13","v0.2.12","v0.2.11","v0.2.10","v0.2.9","v0.2.8","v0.2.7","v0.2.6","v0.2.5","v0.2.4","v0.2.3","v0.2.2","v0.2.1","v0.1.11","v0.1.10","v0.1.9","v0.1.8","v0.1.7","v0.1.6","v0.1.5","v0.1.4","v0.1.3","v0.1.2","v0.1.1","v0.1.0"],"database_specific":{"source":"https://cna.erlef.org/osv/EEF-CVE-2026-77956.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H"}],"credits":[{"name":"Peter Ullrich","type":"FINDER"},{"name":"Peter Ullrich","type":"REPORTER"},{"name":"Zach Daniel / Ash Project","type":"REMEDIATION_DEVELOPER"},{"name":"Jonatan Männchen / EEF","type":"COORDINATOR"}]}