How severe is CVE-2024-45047?

CVE-2024-45047 has a CVSS score of 5.4/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2024-45047?

CVE-2024-45047 affects the following packages: svelte (npm). Ecosystems affected: npm.

How do I fix CVE-2024-45047?

Update svelte to 4.2.19 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-45047 is resolved across your whole dependency graph.

How do I detect CVE-2024-45047 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for svelte. 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-2024-45047 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-2024-45047?

O3 pinpoints whether CVE-2024-45047 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-2024-45047 actively exploited in the wild?

Yes. There are 1 known exploit references for CVE-2024-45047, including 1 in-the-wild exploitation observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2024-45047?

CVE-2024-45047 has an EPSS (Exploit Prediction Scoring System) score of 0.3%, placing it in the 26th 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.

When was CVE-2024-45047 published, and has it been updated?

CVE-2024-45047 was published on August 30, 2024 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-2024-45047: svelte Cross-Site Scripting (Medium 5.4)

EPSS Exploitation Probability

via FIRST.org ↗

0.3%probability of exploitation in next 30 days

Lower Risk26th percentile-0.04%

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

1 pkg affected

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

sveltenpm

4.8Mdownloads / week

Description

svelte performance oriented web framework. A potential mXSS vulnerability exists in Svelte for versions up to but not including 4.2.19. Svelte improperly escapes HTML on server-side rendering. The assumption is that attributes will always stay as such, but in some situation the final DOM tree rendered on browsers is different from what Svelte expects on server-side rendering. This may be leveraged to perform XSS attacks, and a type of the XSS is known as mXSS (mutation XSS). More specifically, this can occur when injecting malicious content into an attribute within a noscript tag. This issue has been addressed in release version 4.2.19. Users are advised to upgrade. There are no known workarounds for this vulnerability.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`svelte`	all versions	4.2.19

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for svelte. 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 svelte to 4.2.19 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2024-45047 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-2024-45047 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-2024-45047. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

svelte performance oriented web framework. A potential mXSS vulnerability exists in Svelte for versions up to but not including 4.2.19. Svelte improperly escapes HTML on server-side rendering. The assumption is that attributes will always stay as such, but in some situation the final DOM tree rendered on browsers is different from what Svelte expects on server-side rendering. This may be leveraged to perform XSS attacks, and a type of the XSS is known as mXSS (mutation XSS). More specifically, this can occur when injecting malicious content into an attribute within a `noscript` tag. This issue

O3 Security · Impact-Aware SCA

Is CVE-2024-45047 in your dependencies?

O3 detects CVE-2024-45047 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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CVE-2024-45047