How severe is CVE-2026-30948?

No CVSS score has been assigned to CVE-2026-30948 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-30948?

CVE-2026-30948 affects the following packages: parse-server (npm), parse-server (npm). Ecosystems affected: npm.

How do I fix CVE-2026-30948?

Update parse-server to 9.5.2-alpha.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-30948 is resolved across your whole dependency graph.

How do I detect CVE-2026-30948 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for parse-server. 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.

How do I mitigate CVE-2026-30948 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.

How does O3 Security protect against CVE-2026-30948?

O3 pinpoints whether CVE-2026-30948 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2026-30948 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-30948 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 CVE-2026-30948?

CVE-2026-30948 has an EPSS (Exploit Prediction Scoring System) score of 0.2%, placing it in the 12th 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 CVE-2026-30948?

CVE-2026-30948 is classified as Cross-site Scripting (XSS) (CWE-79). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2026-30948 published, and has it been updated?

CVE-2026-30948 was published on March 10, 2026 and was last updated on April 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.

CVE-2026-30948: parse-server Cross-Site Scripting

EPSS Exploitation Probability

via FIRST.org ↗

0.2%probability of exploitation in next 30 days

Lower Risk12th percentile+0.19%

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.

Blast Radius

2 pkgs affected

Weekly download volume for affected packages — a proxy for how broadly this vulnerability is deployed.

parse-servernpm

31Kdownloads / week

Description

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 9.5.2-alpha.4 and 8.6.17, a stored cross-site scripting (XSS) vulnerability allows any authenticated user to upload an SVG file containing JavaScript. The file is served inline with Content-Type: image/svg+xml and without protective headers, causing the browser to execute embedded scripts in the Parse Server origin. This can be exploited to steal session tokens from localStorage and achieve account takeover. The default fileExtensions option blocks HTML file extensions but does not block SVG, which is a well-known XSS vector. All Parse Server deployments where file upload is enabled for authenticated users (the default) are affected. This vulnerability is fixed in 9.5.2-alpha.4 and 8.6.17.

Affected Packages

2 total 2 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`parse-server`	≥ 9.0.0&&< 9.5.2-alpha.4	9.5.2-alpha.4
📦npm	`parse-server`	all versions	8.6.17

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for parse-server. 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 parse-server to 9.5.2-alpha.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-30948 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 CVE-2026-30948 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 CVE-2026-30948. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to 9.5.2-alpha.4 and 8.6.17, a stored cross-site scripting (XSS) vulnerability allows any authenticated user to upload an SVG file containing JavaScript. The file is served inline with Content-Type: image/svg+xml and without protective headers, causing the browser to execute embedded scripts in the Parse Server origin. This can be exploited to steal session tokens from localStorage and achieve account takeover. The default fileExtensions option blocks HTML file extensions but does not

O3 Security · Impact-Aware SCA

Is CVE-2026-30948 in your dependencies?

O3 detects CVE-2026-30948 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works

CVE-2026-30948