EEx template evaluation of prompt content in AshAi enables remote code execution (CVE-2026-77956) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-77956

EEx template evaluation of prompt content in AshAi enables remote code execution

Answer in brief

CVE-2026-77956 records a Unknown severity vulnerability in EEx template evaluation of prompt content in AshAi enables remote code execution. The current sources do not mark it as known exploited. The current feed maps ash-project/ash_ai (generic), ash-project/ash_ai (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Aug 31, 2026Updated Aug 31, 2026Source checked Aug 31, 2026First seen by HOL Aug 31, 2026Material review Aug 31, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 2 mapped packages or products
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps ash-project/ash_ai (generic), ash-project/ash_ai (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
ash-project/ash_aigeneric	>=0.1.0 <1.0.0	1.0.0
ash-project/ash_aigeneric	>=4aab131d40a0bd5a8cf0b3c4eaaa59d49565f3d1 <e9948254b5659c1143b73dc2f59f457931e64514	e9948254b5659c1143b73dc2f59f457931e64514

Recommended response

Check inventory. Check lockfiles and deployed manifests for ash-project/ash_ai, ash-project/ash_ai.
Review the reported fix. Update ash-project/ash_ai to 1.0.0; ash-project/ash_ai to e9948254b5659c1143b73dc2f59f457931e64514 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Aug 31, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 31, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 31, 2026

Sources and claim methodology

Upstream source 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.

Quoted source text, attributed separately from HOL analysis.