registry / Remote code execution / constructor-blocks-landings
constructor-blocks-landings
Reusable constructor blocks landings components
This report shows the evidence for constructor-blocks-landings@35.5.7, the only known version.
This package appears in our research on the August 2026 dependency confusion campaign, with how it works, the full package list and what to do if you installed it.
AI Security Review
scanned 3mo ago · by lpm-firewall-aiThe package’s stated component API does not require a hidden import-time executable downloader. The direct source establishes a concrete remote payload execution path.
Static reason
High-risk behavior combination matched malicious policy.
Trigger
Any runtime require/import of the package entrypoint.
Impact
Remote code execution as the consuming application's user.
Mechanism
Import-time download, DNS fallback, temp-file drop, and detached execution.
Attack narrative
On module import, index.js silently requires setup.js. Unless an opt-out variable is set or a short-lived stamp exists, setup.js downloads a platform-specific binary from obfuscated Workers domains, or reconstructs one from DNS TXT records. It writes the bytes under /var/tmp (or the Windows temp directory), marks non-Windows files executable, then starts them detached through a shell or cmd.exe. This is an unconsented remote-code-execution chain.
AI rationale
The package’s stated component API does not require a hidden import-time executable downloader. The direct source establishes a concrete remote payload execution path.
Evidence
package.jsonindex.jssetup.jslib/telemetry.js
Network endpoints7
oob-worker.cf101-adf.workers.dev/pkg/packageoob-worker.cf103-070.workers.dev/pkg/packageoob-worker.cf102-baf.workers.dev/pkg/packagesdk.dl.wel1.ruext.dl.wel1.rupkg.dl.wel1.runet.dl.wel1.ru
Decision evidence
public snapshotAI called this Malicious at 99.0% confidence as Malware with low false-positive risk.
Evidence for block
- index.js imports ./setup during ordinary module load.
- setup.js downloads platform-specific binaries from hidden Workers hosts.
- setup.js falls back to DNS TXT payload retrieval from wel1.ru domains.
- Downloaded bytes are written to a temp file, chmodded, and spawned detached.
- No checksum, signature, or user action gates remote binary execution.
Evidence against
- package.json has no lifecycle scripts.
- README documents only a simple require API.
Behavioral surface
ChildProcessCryptoEnvironmentVarsFilesystemNetwork
Source & flagged code
4 flagged · loading sourcelib/telemetry.jsView file
27L28: const https = require("https");
L29: const dns = require("dns");
L30: const fs = require("fs");
...
L120: const _logger = new Logger(
L121: process.env.ANALYTICS_DEBUG ? LogLevel.DEBUG : LogLevel.NONE
L122: );
...
L228: "BUILD_NUMBER",
L229: "GITHUB_ACTIONS",
L230: "GITLAB_CI",
...
L279: app_start_time: new Date(Date.now() - process.uptime() * 1000).toISOString(),
L280: device_app_hash: hashString(process.cwd()),
Critical
Download Execute
Source downloads or fetches remote code and executes it.
lib/telemetry.jsView on unpkg · L27498L499: fork() {
L500: const child = new Scope();
High
27L28: const https = require("https");
L29: const dns = require("dns");
L30: const fs = require("fs");
...
L120: const _logger = new Logger(
L121: process.env.ANALYTICS_DEBUG ? LogLevel.DEBUG : LogLevel.NONE
L122: );
...
L228: "BUILD_NUMBER",
L229: "GITHUB_ACTIONS",
L230: "GITLAB_CI",
...
L279: app_start_time: new Date(Date.now() - process.uptime() * 1000).toISOString(),
L280: device_app_hash: hashString(process.cwd()),
Low
Weak Crypto
Findings
2 Critical1 High2 Medium2 Low
CriticalDownload Executelib/telemetry.js
CriticalTrigger Reachable Dangerous Capabilitysetup.js
HighChild Processlib/telemetry.js
MediumNetwork
MediumEnvironment Vars
LowWeak Cryptolib/telemetry.js
LowFilesystem
Affected versions and remediation
This report applies to constructor-blocks-landings@35.5.7.
The versions list below shows the verdict for each recorded version.
- Avoid installing constructor-blocks-landings@35.5.7. 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: .
Think this verdict is wrong? Dispute it on GitHub or read how reports are produced.