registry / Credential exfiltration / fca-nx / 6.7.1

fca-nx@6.7.1

Facebook Messenger API for Node.js — Fast, Secure, and Feature-Rich

AI Security Review

scanned 1mo ago · by lpm-firewall-ai

This is a dangerous opt-in capability rather than confirmed malware: it forwards an existing service session to unrestricted operator-configured endpoints. The explicit gate prevents treating it as covert default theft, but it does not bind the destination to Facebook.

Static reason

High-risk behavior combination matched malicious policy.; source matched previously finalized malicious package; routed for review; previous stored version diff introduced dangerous source

Trigger

Set FB_DGW_ENABLE to 1 and provide at least one FB_DGW_URL_* value before the E2EE client connects.

Impact

An operator-configured non-Facebook endpoint can receive the authenticated Facebook session cookies.

Mechanism

The client serializes its application-state cookies, then opens WebSockets to the configured URLs with that value in the Cookie header.

AI rationale

Evidence

src/api/socket/e2ee/vendor/fb-e2ee.cjs

Decision evidence

public snapshot

AI called this Suspicious at 94.0% confidence as Dangerous Capability with low false-positive risk.

Evidence for warning

An opt-in environment flag enables a DGW connection using operator-supplied endpoint URLs.
The connection builds a Cookie header from the active Facebook application state and supplies it to every configured WebSocket URL.
The DGW connection is invoked after E2EE startup, so the forwarding path is reachable when enabled.

Evidence against

The manifest has no preinstall, install, or postinstall lifecycle hook.
The conventional thread and user lookup code sends requests only to Facebook endpoints.

Behavioral surface

Source

CryptoDynamicRequireEnvironmentVarsFilesystemNetworkWebSocket

Supply chain

HighEntropyStringsUrlStrings

ManifestNo manifest risk signals triggered.

scanned 138 file(s), 966 KB of source, external domains: facebook.com, github.com, graph.facebook.com, m.facebook.com, reg-e2ee.facebook.com, registry.npmjs.org, static.xx.fbcdn.net, upload.facebook.com, www.facebook.com, www.messenger.com, www.whatsapp.com

Source & flagged code

8 flagged

src/api/socket/e2ee/vendor/fb-e2ee.cjsView file

Lines 110-150javascript

110var require_safe_buffer = __commonJS({

111 "node_modules/ws/node_modules/safe-buffer/index.js"(exports2, module2) {

112 "use strict";

113 init_cjs_shims();

114 var buffer = require("buffer");

115 var Buffer3 = buffer.Buffer;

116 function copyProps(src, dst) {

117 for (var key in src) {

118 dst[key] = src[key];

119 }

120 }

121 if (Buffer3.from && Buffer3.alloc && Buffer3.allocUnsafe && Buffer3.allocUnsafeSlow) {

122 module2.exports = buffer;

123 } else {

124 copyProps(buffer, exports2);

125 exports2.Buffer = SafeBuffer;

126 }

127 function SafeBuffer(arg, encodingOrOffset, length) {

128 return Buffer3(arg, encodingOrOffset, length);

129 }

130 copyProps(Buffer3, SafeBuffer);

131 SafeBuffer.from = function(arg, encodingOrOffset, length) {

132 if (typeof arg === "number") {

Critical

Hardcoded Runtime Data Exfiltration

Source sends credentials or rich application records to a package-controlled external receiver enabled by default.

src/api/socket/e2ee/vendor/fb-e2ee.cjsView on unpkg · L130

Low

Weak Crypto

Package source references weak cryptographic algorithms.

src/api/socket/e2ee/vendor/fb-e2ee.cjsView on unpkg · L130

133 throw new TypeError("Argument must not be a number");

134 }

135 return Buffer3(arg, encodingOrOffset, length);

136 };

137 SafeBuffer.alloc = function(size, fill, encoding) {

138 if (typeof size !== "number") {

139 throw new TypeError("Argument must be a number");

140 }

141 var buf = Buffer3(size);

142 if (fill !== void 0) {

143 if (typeof encoding === "string") {

144 buf.fill(fill, encoding);

145 } else {

146 buf.fill(fill);

147 }

148 } else {

149 buf.fill(0);

150 }

Lines 2944-2984javascript

2944 "kyc-id",

2945 "privacy_token",

2946 "readreceipts",

2947 "appointment_only",

2948 "address",

2949 "expected_ts",

2950 "privacy",

2951

module/loginHelper.jsView file

Lines 1-21javascript

1"use strict";

2const fs = require("fs");

3const path = require("path");

Medium

Dynamic Require

Package source references dynamic require/import behavior.

module/loginHelper.jsView on unpkg · L1

src/api/threads/getThreadInfo.jsView file

•matchType = normalized_sha256 matchedPackage = fcanew-r3nz75@10.1.15 matchedPath = src/api/threads/getThreadInfo.js matchedIdentity = npm:ZmNhbmV3LXIzbno3NQ:10.1.15 similarity = 1.000 summary = normalized source hash matched finalized malicious source

High

Known Malware Source Similarity

Source file is highly similar to a previously finalized malicious package; route for source-aware review.

src/api/threads/getThreadInfo.jsView on unpkg

src/api/users/getUserInfo.jsView file

•matchType = normalized_sha256 matchedPackage = @eryxenx/fca@1.0.5 matchedPath = src/api/users/getUserInfo.js matchedIdentity = npm:QGVyeXhlbngvZmNh:1.0.5 similarity = 1.000 summary = normalized source hash matched finalized malicious source

High

Known Malware Source Similarity

Source file is highly similar to a previously finalized malicious package; route for source-aware review.

src/api/users/getUserInfo.jsView on unpkg

Source & flagged code

8 flagged · loading source

src/api/socket/e2ee/vendor/fb-e2ee.cjsView file

130copyProps(Buffer3, SafeBuffer); L131: SafeBuffer.from = function(arg, encodingOrOffset, length) { L132: if (typeof arg === "number") { ... L400: * @return {Object} Accepted configuration L401: * @private L402: */ ... L543: this._inflate[kWriteInProgress] = true; L544: this._inflate.write(data); L545: if (fin) this._inflate.write(TRAILER); ... L660: * @param {(String|Buffer|ArrayBuffer|Buffer[])} data The received data L661: * @param {WebSocket} target A reference to the target to which the event was dispatched L662: */

Critical

Hardcoded Runtime Data Exfiltration

Source sends credentials or rich application records to a package-controlled external receiver enabled by default.

src/api/socket/e2ee/vendor/fb-e2ee.cjsView on unpkg · L130

2964patternName = google_api_key severity = high line = 2964

High

High Secret

Package contains a high-severity secret pattern.

src/api/socket/e2ee/vendor/fb-e2ee.cjsView on unpkg · L2964

2964patternName = google_api_key severity = high line = 2964

High

Secret Pattern

Findings

1 Critical5 High4 Medium5 Low

CriticalHardcoded Runtime Data Exfiltrationsrc/api/socket/e2ee/vendor/fb-e2ee.cjs

HighHigh Secretsrc/api/socket/e2ee/vendor/fb-e2ee.cjs

HighKnown Malware Source Similaritysrc/api/threads/getThreadInfo.js

HighKnown Malware Source Similaritysrc/api/users/getUserInfo.js

HighPrevious Version Dangerous Deltamodule/loginHelper.js

HighSecret Patternsrc/api/socket/e2ee/vendor/fb-e2ee.cjs

MediumDynamic Requiremodule/loginHelper.js

MediumNetwork

MediumEnvironment Vars

MediumStructural Risk Force Deep Review

LowScripts Present

LowWeak Cryptosrc/api/socket/e2ee/vendor/fb-e2ee.cjs

Affected versions and remediation

This report applies to fca-nx@6.7.1.

See all versions of fca-nx for other recorded verdicts.

Review the evidence and your use of fca-nx@6.7.1 before allowing it. Restrict the permissions described in this report.
Choose an independently verified alternative or release. This report does not establish that other versions are safe.

Evidence last updated: 2026-09-20 19:30:12.261Z (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

Runtime surface

Behavioral surface

Source & flagged code