GHSA-7gmj-h9xc-mcxc is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in mailparser. A fix is available for mailparser — see the affected versions and patch details below.
mailparser vulnerable to Cross-site Scripting
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
Exploitation and automatability from CISA’s SSVC triage for GHSA-7gmj-h9xc-mcxc.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-7gmj-h9xc-mcxc plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
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.
mailparsernpmDescription
Versions of the package mailparser before 3.9.3 are vulnerable to Cross-site Scripting (XSS) via the textToHtml() function due to the improper sanitisation of URLs in the email content. An attacker can execute arbitrary scripts in victim browsers by adding extra quote " to the URL with embedded malicious JavaScript code.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | mailparser | all versions | 3.9.3npm install mailparser@3.9.3 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for mailparser, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update mailparser to 3.9.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-7gmj-h9xc-mcxc 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.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-7gmj-h9xc-mcxc can be triaged on real exposure rather than presence alone.
Tailored to GHSA-7gmj-h9xc-mcxc. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-7gmj-h9xc-mcxc in your dependencies?
O3 Security finds GHSA-7gmj-h9xc-mcxc across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.