Elo backends have code injection via unvalidated emission of programmatic AST fields

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

7.4 · CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

No dated EPSS signal available.

As published by the source; long descriptions are shortened.

Summary Elo's programmatic AST API accepts arbitrary values in many node fields without runtime type or syntax validation. Each backend's emit stage interpolates those values straight into the generated source with no escape pass. An integrator that populates the AST from JSON-deserialised input, plugin output, or any other untyped source therefore exposes a code-injection primitive that flows through to the emitted JavaScript, Ruby, Python, or SQL. The same pattern was previously addressed in 0.9.7 (2026-01-27), which patched the date/datetime/duration literal emitters via `JSON.stringify()` after a report by naoyashiga. This advisory generalises that fix to the remaining AST surface — at least 23 emission sites across six node-field categories and four backends.

Vulnerable sinks Each row is a category of sinks that share the same shape: TypeScript signature erased at runtime → AST-API consumer passes a crafted value → emit interpolates the value verbatim. |

| AST…

Published by the source

3 Nov 2026, 17:48 UTC

Last modified by the source

3 Nov 2026, 18:02 UTC

Source last checked

4 Nov 2026, 06:10 UTC

1. Revision 2 · amended · 4 Nov 2026

   Amended from osv record GHSA-x9rp-7wh3-2rj5

2. Revision 1 · created · 3 Nov 2026

   Published from ghsa record GHSA-x9rp-7wh3-2rj5

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# Patch Next advisory brief: CVE-2026-44265

Advisory: Elo backends have code injection via unvalidated emission of programmatic AST fields
IDs: CVE-2026-44265, GHSA-x9rp-7wh3-2rj5
Record: https://patchnext.com/advisories/cve-2026-44265 (revision 2, source checked 4 Nov 2026, 06:10 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.4)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: @enspirit/elo 1.0.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm @enspirit/elo: affected < 1.0.1; fixed in 1.0.1

## Suggested inspection (read-only)
- `npm ls @enspirit/elo --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on @enspirit/elo.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-x9rp-7wh3-2rj5 (GitHub-reviewed advisory GHSA-x9rp-7wh3-2rj5 lists affected ranges: npm @enspirit/elo >=0 <=1.0.0)
- Verified: https://osv.dev/vulnerability/GHSA-x9rp-7wh3-2rj5 (OSV record GHSA-x9rp-7wh3-2rj5 lists affected ranges: npm @enspirit/elo >=0 <1.0.1 (fixed))

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