GHSA-36xv-jgw5-4q75 is a medium-severity (CVSS 6.1) CWE-74 vulnerability in @nestjs/core. O3 Security confirms whether GHSA-36xv-jgw5-4q75 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
@nestjs/core Improperly Neutralizes Special Elements in Output Used by a Downstream Component ('Injection')
Real-World Exposure
@nestjs/coreReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects npm packages — download data is not available via public APIs for these ecosystems.
Description
Impact
What kind of vulnerability is it? Who is impacted?
SseStream._transform() interpolates message.type and message.id directly into Server-Sent Events text protocol output without sanitizing newline characters (\r, \n). Since the SSE protocol treats both \r and \n as field delimiters and \n\n as event boundaries, an attacker who can influence these fields through upstream data sources can inject arbitrary SSE events, spoof event types, and corrupt reconnection state. Spring Framework's own security patch (6e97587) validates these same fields (id, event) for the same reason.
Actual impact:
- Event spoofing: Attacker forges SSE events with arbitrary
event:types, causing client-sideEventSource.addEventListener()callbacks to fire for wrong event types. - Data injection: Attacker injects arbitrary
data:payloads, potentially triggering XSS if the client renders SSE data as HTML without sanitization. - Reconnection corruption: Attacker injects
id:fields, corrupting theLast-Event-IDheader on reconnection, causing the client to miss or replay events. - Attack precondition: Requires the developer to map user-influenced data to the
typeoridfields of SSE messages. Direct HTTP request input does not reach these fields without developer code bridging the gap.
Patches
Has the problem been patched? What versions should users upgrade to?
Patched in @nestjs/[email protected]
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | @nestjs/core | all versions | 11.1.18 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @nestjs/core. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update @nestjs/core to 11.1.18 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-36xv-jgw5-4q75 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 pinpoints whether GHSA-36xv-jgw5-4q75 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-36xv-jgw5-4q75. 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-36xv-jgw5-4q75 in your dependencies?
O3 detects GHSA-36xv-jgw5-4q75 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.