CVE-2026-27492
Lettermint Node.js SDK leaks email properties to unintended recipients when client instance is reused
Description
### Impact Email properties (such as to, subject, html, text, and attachments) are not reset between sends when a single client instance is reused across multiple .send() calls. This can cause properties from a previous send to leak into a subsequent one, potentially delivering content or recipient addresses to unintended parties. Applications sending emails to different recipients in sequence — such as transactional flows like password resets or notifications — are affected. ### Patches Yes, the issue has been patched. Users should upgrade to v1.5.1 or later. ### Workarounds If upgrading immediately is not possible, instantiate a new client for each send: ```js const client = new Lettermint({ apiKey: process.env.LETTERMINT_API_KEY }); await client.email.to('...').subject('...').html('...').send(); ``` This ensures no state is carried over between sends.
How to fix CVE-2026-27492
To remediate CVE-2026-27492, upgrade the affected package to a fixed version below.
- —upgrade to 1.5.1 or later
Is CVE-2026-27492 being exploited?
Low — EPSS is 0.0%, meaning exploitation activity has not been observed at scale.
Affected packages (1)
- from 0, < 1.5.1
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | MEDIUM4.7 | CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N |