How severe is GHSA-49pc-8936-wvfp?

GHSA-49pc-8936-wvfp has a CVSS score of 4.7/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-49pc-8936-wvfp?

GHSA-49pc-8936-wvfp affects the following packages: lettermint (npm). Ecosystems affected: npm.

How do I fix GHSA-49pc-8936-wvfp?

Update lettermint to 1.5.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-49pc-8936-wvfp is resolved across your whole dependency graph.

How do I detect GHSA-49pc-8936-wvfp in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for lettermint, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate GHSA-49pc-8936-wvfp if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Is GHSA-49pc-8936-wvfp actively exploited in the wild?

No public exploit code has been indexed for GHSA-49pc-8936-wvfp yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-49pc-8936-wvfp?

GHSA-49pc-8936-wvfp has an EPSS (Exploit Prediction Scoring System) score of 0.2%, placing it in the 8th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-49pc-8936-wvfp?

GHSA-49pc-8936-wvfp is classified as CWE-488 (CWE-488). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-49pc-8936-wvfp published, and has it been updated?

GHSA-49pc-8936-wvfp was published on February 20, 2026 and was last updated on February 23, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦

📦 npm

Not in CISA KEV

MEDIUM severity

Lettermint Node.js SDK leaks email properties to unintended recipients when client instance is reusedGHSA-49pc-8936-wvfp

MEDIUMFix: lettermint/lettermint-node@24a17ac

GHSA-49pc-8936-wvfp is a medium-severity (CVSS 4.7) CWE-488 vulnerability in lettermint. A fix is available for lettermint — see the affected versions and patch details below.

Also known asCVE-2026-27492

Published

Feb 20, 2026

Updated

Feb 23, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 10, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for GHSA-49pc-8936-wvfp.

EPSS Exploitation Probability

via FIRST.org ↗

0.2%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs8th percentile — riskier than 8% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

1 pkg affected

How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.

3other npm packages depend on this — each one inherits the vulnerability until it's patched upstream

lettermintnpm

27Kdownloads / week

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:

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.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`lettermint`	all versions	1.5.1`npm install lettermint@1.5.1`

Affected Products

1 product · 1 configurations

Application

lettermintlettermint

< 1.5.1

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for lettermint, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update lettermint to 1.5.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-49pc-8936-wvfp is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Frequently Asked Questions

### 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 im