How severe is CVE-2026-43897?

No CVSS score has been assigned to CVE-2026-43897 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-43897?

CVE-2026-43897 affects the following packages: link-preview-js (npm). Ecosystems affected: npm.

How do I fix CVE-2026-43897?

Update link-preview-js to 4.0.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-43897 is resolved across your whole dependency graph.

How do I detect CVE-2026-43897 in my npm dependencies?

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

How do I mitigate CVE-2026-43897 if there is no patch (or I can't update yet)?

Restrict outbound requests from the affected component to an allowlist of hosts, block access to link-local and internal address ranges at the network layer, and require authentication on internal services so a forged request cannot reach them unauthenticated.

Is CVE-2026-43897 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-43897 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-2026-43897?

CVE-2026-43897 has an EPSS (Exploit Prediction Scoring System) score of 0.7%, placing it in the 52th 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-2026-43897?

CVE-2026-43897 is classified as Server-Side Request Forgery (SSRF) (CWE-918). 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-2026-43897 published, and has it been updated?

CVE-2026-43897 was published on May 11, 2026 and was last updated on October 28, 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-2026-43897 — link-preview-js

Fix: OP-Engineering/link-preview-js@4396d48

CVE-2026-43897 is a Server-Side Request Forgery (SSRF) vulnerability in link-preview-js. A fix is available for link-preview-js — see the affected versions and patch details below.

Link Preview JS: vunerable to IPv6 and internal loopback attacks

Also known asGHSA-4gp8-rjrq-ch6q

Published

May 11, 2026

Updated

Oct 28, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 7, 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-2026-43897.

EPSS Exploitation Probability

via FIRST.org ↗

0.7%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs52th percentile — riskier than 52% 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.

179other npm packages depend on this — each one inherits the vulnerability until it's patched upstream

link-preview-jsnpm

227Kdownloads / week

Description

Impact

The library did not check for IPv6 loopback attacks. There was also a DNS attack, where an address could be resolved into an internal IP. This could cause internal data leaks.

Patches

Problem has been patched in version 4.0.1. However, it cannot be completely solved by the package alone. The regex used for validation has been tightened for IPv6 addresses.

The DNS resolving, however, is more difficult. The regex has been tightened to prohibit .internal, .local, .nip.io and .sslip.io addresses, however there can be other services not on the list, therefore it is imperative that users use the resolveDNSHost option to do DNS resolution before fetching content. To that regard a (scary) error message has been added when the option is not set.

Workarounds

Users can do their own validation before fetching content.

Reported by https://github.com/Andrew-most-likely

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`link-preview-js`	all versions	4.0.1`npm install link-preview-js@4.0.1`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for link-preview-js, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update link-preview-js to 4.0.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-43897 is resolved across your whole dependency graph.
Workarounds
Restrict outbound requests from the affected component to an allowlist of hosts, block access to link-local and internal address ranges at the network layer, and require authentication on internal services so a forged request cannot reach them unauthenticated.

Frequently Asked Questions

### Impact The library did not check for IPv6 loopback attacks. There was also a DNS attack, where an address could be resolved into an internal IP. This could cause internal data leaks. ### Patches Problem has been patched in version 4.0.1. However, it cannot be completely solved by the package alone. The regex used for validation has been tightened for IPv6 addresses. The DNS resolving, however, is more difficult. The regex has been tightened to prohibit .internal, .local, .nip.io and .sslip.io addresses, however there can be other services not on the list, therefore it is imperative that

O3 Security · Impact-Aware SCA

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