How severe is GHSA-9v98-6g37-x9g6?

GHSA-9v98-6g37-x9g6 has a CVSS score of 9.9/10, rated CRITICAL. Immediate patching is strongly recommended.

Which packages are affected by GHSA-9v98-6g37-x9g6?

GHSA-9v98-6g37-x9g6 affects the following packages: @deepstream/server (npm). Ecosystems affected: npm.

How do I fix GHSA-9v98-6g37-x9g6?

Update @deepstream/server to 10.0.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-9v98-6g37-x9g6 is resolved across your whole dependency graph.

How do I detect GHSA-9v98-6g37-x9g6 in my npm dependencies?

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

How do I mitigate GHSA-9v98-6g37-x9g6 if there is no patch (or I can't update yet)?

Close the privilege gap rather than the entry point: audit which accounts, roles and service identities can reach the affected operation, drop the component to the least privilege it actually needs, and review file and directory permissions created by earlier installs — a default left in place is what makes this reachable.

Is GHSA-9v98-6g37-x9g6 actively exploited in the wild?

No public exploit code has been indexed for GHSA-9v98-6g37-x9g6 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-9v98-6g37-x9g6?

GHSA-9v98-6g37-x9g6 has an EPSS (Exploit Prediction Scoring System) score of 0.5%, placing it in the 38th 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-9v98-6g37-x9g6?

GHSA-9v98-6g37-x9g6 is classified as CWE-1321 (CWE-1321). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-9v98-6g37-x9g6 published, and has it been updated?

GHSA-9v98-6g37-x9g6 was published on June 26, 2026 and was last updated on September 10, 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

CRITICAL severity

GHSA-9v98-6g37-x9g6 — @deepstream/server

CRITICALFix: deepstreamIO/deepstream.io@54b8e29

GHSA-9v98-6g37-x9g6 is a critical-severity (CVSS 9.9) CWE-1321 vulnerability in @deepstream/server. A fix is available for @deepstream/server — see the affected versions and patch details below.

deepstream is vulnerable to prototype pollution

Also known asCVE-2026-49252

Published

Jun 26, 2026

Updated

Sep 10, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Sep 27, 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-9v98-6g37-x9g6.

EPSS Exploitation Probability

via FIRST.org ↗

0.5%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs38th percentile — riskier than 38% of all scored CVEsHighest risk

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

How urgent is this, really

GHSA-9v98-6g37-x9g6 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.

Where this sits among everything scored

Of 379,842 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.

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.

6other npm packages depend on this — each one inherits the vulnerability until it's patched upstream

@deepstream/servernpm

461downloads / week

Description

Impact

Prototype pollution in deepstream server v <=10.0.4. Potential privilege escalation from any authenticated user with write permission to any record.

Patches

Yes, upgrade to v10.0.5

Workarounds

Filter out all messages containing the path __proto__, constructor, prototype, before they reach the server's message pipeline

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`@deepstream/server`	all versions	10.0.5`npm install @deepstream/server@10.0.5`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @deepstream/server, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update @deepstream/server to 10.0.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-9v98-6g37-x9g6 is resolved across your whole dependency graph.
Workarounds
Close the privilege gap rather than the entry point: audit which accounts, roles and service identities can reach the affected operation, drop the component to the least privilege it actually needs, and review file and directory permissions created by earlier installs — a default left in place is what makes this reachable.

Frequently Asked Questions

### Impact Prototype pollution in deepstream server v <=10.0.4. Potential privilege escalation from any authenticated user with write permission to any record. ### Patches Yes, upgrade to v10.0.5 ### Workarounds Filter out all messages containing the path `__proto__`, `constructor`, `prototype`, **before they reach the server's message pipeline**