How severe is CVE-2023-45311?

CVE-2023-45311 has a CVSS score of 9.8/10, rated CRITICAL. Immediate patching is strongly recommended.

Which packages are affected by CVE-2023-45311?

CVE-2023-45311 affects the following packages: fsevents (npm). Ecosystems affected: npm.

How do I fix CVE-2023-45311?

Update fsevents to 1.2.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-45311 is resolved across your whole dependency graph.

How do I detect CVE-2023-45311 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for fsevents. 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-2023-45311 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-2023-45311?

O3 pinpoints whether CVE-2023-45311 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-2023-45311 actively exploited in the wild?

Yes. There are 6 known exploit references for CVE-2023-45311, including 6 in-the-wild exploitations 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-2023-45311?

CVE-2023-45311 has an EPSS (Exploit Prediction Scoring System) score of 1.5%, placing it in the 72th 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-2023-45311 published, and has it been updated?

CVE-2023-45311 was published on October 6, 2023 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.

📦 npm

CVE-2023-45311

CRITICAL

Code injection in fsevents

Also known asGHSA-8r6j-v8pm-fqw3

Published

Oct 6, 2023

Updated

Apr 10, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

6 known

EPSS Exploitation Probability

via FIRST.org ↗

1.5%probability of exploitation in next 30 days

Lower Risk72th percentile+0.65%

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.

fseventsnpm

33.2Mdownloads / week

Description

fsevents before 1.2.11 depends on the https://fsevents-binaries.s3-us-west-2.amazonaws.com URL, which might allow an adversary to execute arbitrary code if any JavaScript project (that depends on fsevents) distributes code that was obtained from that URL at a time when it was controlled by an adversary. NOTE: some sources feel that this means that no version is affected any longer, because the URL is not controlled by an adversary.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`fsevents`	all versions	1.2.11

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.