ip-address: Address6.isLinkLocal() recognizes fe80::/64 rather than fe80::/10, allowing SSRF and trust-boundary bypass to on-link hosts (CVE-2026-101913) | HOL Guard CVE

Medium · CVSS 6.3CVE-2026-101913

ip-address: Address6.isLinkLocal() recognizes fe80::/64 rather than fe80::/10, allowing SSRF and trust-boundary bypass to on-link hosts

Answer in brief

CVE-2026-101913 records a Medium severity (CVSS 6.3) vulnerability in ip-address: Address6.isLinkLocal() recognizes fe80::/64 rather than fe80::/10, allowing SSRF and trust-boundary bypass to on-link hosts. The current sources do not mark it as known exploited. The current feed maps beaugunderson/ip-address (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 28, 2026Updated Sep 28, 2026Source checked Sep 28, 2026First seen by HOL Sep 28, 2026Material review Sep 28, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 6.3
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 6.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps beaugunderson/ip-address (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
beaugunderson/ip-addressgeneric	<10.5.1	10.5.1

Recommended response

Check inventory. Check lockfiles and deployed manifests for beaugunderson/ip-address.
Review the reported fix. Update beaugunderson/ip-address to 10.5.1 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 28, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 28, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 28, 2026

Sources and claim methodology

Upstream source description

ip-address is a library for parsing and manipulating IPv4 and IPv6 addresses in JavaScript. Prior to 10.5.1, the Address6 isLinkLocal method in src/ipv6.ts recognizes only fe80::/64 instead of the complete fe80::/10 IPv6 link-local range. An attacker-controlled address elsewhere in fe80::/10 can therefore pass a trust-boundary check that relies on isLinkLocal. The same address is identified as link-local by getType and getScope, exposing the inconsistent classification. A successful bypass can reach an on-link host outside the intended trust boundary. This issue is fixed in version 10.5.1.

Quoted source text, attributed separately from HOL analysis.