High severity · published Aug 31, 2026
CVE-2026-77956
EEx template evaluation of prompt content in AshAi enables remote code execution
8.9
CVSS
0.3%
EPSS
No
On KEV
Description
Improper Control of Generation of Code (Code Injection) vulnerability in ash-project ash_ai allows a remote, unauthenticated client to execute arbitrary Elixir code.
AshAi.Actions.Prompt evaluates prompt content through EEx.eval_string/2. The documented prompt: fn input, context -> ... 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 <%= System.cmd(...) %> 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.
This issue affects ash_ai: from 0.1.0 before 1.0.0.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 21% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AS
ash_ai · ash-project
0.1.0 before 1.0.0; 4aab131d40a0bd5a8cf0b3c4eaaa59d49565f3d1 before e9948254b5659c1143b73dc2f59f457931e64514 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-77956
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-77956
cna.erlef.org
https://cna.erlef.org/cves/CVE-2026-77956.html
github.com
https://github.com/ash-project/ash_ai/commit/e9948254b5659c1143b73dc2f59f457931e64514
github.com
https://github.com/ash-project/ash_ai/security/advisories/GHSA-2g59-hg7m-qc83
osv.dev
https://osv.dev/vulnerability/EEF-CVE-2026-77956
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