How severe is CVE-2026-45577?

No CVSS score has been assigned to CVE-2026-45577 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-45577?

CVE-2026-45577 affects the following packages: neotoma (npm). Ecosystems affected: npm.

How do I fix CVE-2026-45577?

Update neotoma to 0.11.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-45577 is resolved across your whole dependency graph.

How do I detect CVE-2026-45577 in my npm dependencies?

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

How do I mitigate CVE-2026-45577 if there is no patch (or I can't update yet)?

Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.

Is CVE-2026-45577 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-45577 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-2026-45577?

CVE-2026-45577 has an EPSS (Exploit Prediction Scoring System) score of 0.4%, placing it in the 34th 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-2026-45577?

CVE-2026-45577 is classified as CWE-288 (CWE-288), Missing Authentication (CWE-306). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-45577 published, and has it been updated?

CVE-2026-45577 was published on May 29, 2026 and was last updated on August 12, 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

CVE-2026-45577 — neotoma

CVE-2026-45577 is a CWE-288 vulnerability in neotoma. A fix is available for neotoma — see the affected versions and patch details below.

Neotoma: Unauthenticated Inspector/API access via reverse-proxy loopback auth bypass

Also known asGHSA-5cvp-p7p4-mcx9

Published

May 29, 2026

Updated

Aug 12, 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 assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
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 CVE-2026-45577.

EPSS Exploitation Probability

via FIRST.org ↗

0.4%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs34th percentile — riskier than 34% of all scored CVEsHighest risk

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

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.

0other npm packages depend on this — each one inherits the vulnerability until it's patched upstream

neotomanpm

74downloads / week

Description

Neotoma versions starting at v0.6.0 can treat public reverse-proxied requests as local when the app receives them over a loopback socket and no Bearer token is present.

In affected deployments, the REST auth middleware can resolve unauthenticated requests as the local development user, making the hosted Inspector and related API surface reachable without credentials.

Impact: unauthorized access to production data exposed through the Inspector/API on affected deployments.

Affected condition: a public deployment behind a reverse proxy or same-host tunnel that forwards traffic to the Node process over loopback.

Remediation implemented on the main branch: local-request detection now fails closed in production unless loopback trust is explicitly enabled, and forwarded public clients remain remote.

Patched release version is pending; this draft will be updated once the fix is released.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`neotoma`	≥ 0.6.0&&< 0.11.1	0.11.1`npm install neotoma@0.11.1`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for neotoma, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update neotoma to 0.11.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-45577 is resolved across your whole dependency graph.
Workarounds
Put an independent control in front of the weakness: restrict the affected endpoint or interface to trusted networks, require an additional authentication factor or proxy-level check, and invalidate existing sessions and credentials in case the flaw has already been used.

Frequently Asked Questions

Neotoma versions starting at v0.6.0 can treat public reverse-proxied requests as local when the app receives them over a loopback socket and no Bearer token is present. In affected deployments, the REST auth middleware can resolve unauthenticated requests as the local development user, making the hosted Inspector and related API surface reachable without credentials. Impact: unauthorized access to production data exposed through the Inspector/API on affected deployments. Affected condition: a public deployment behind a reverse proxy or same-host tunnel that forwards traffic to the Node proc

O3 Security · Impact-Aware SCA

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