CVE-2025-6547: Pbkdf2 Pbkdf2 Silently Disregards Uint8Array Input, Vulnerability
CRITICALCVE-2025-6547 is a CRITICAL pbkdf2 silently disregards uint8array input, vulnerability (CWE-20: Improper Input Validation) affecting Pbkdf2 libraries in the npm ecosystem. The issue involves pbkdf2 silently disregards uint8array input, returning static keys. Remediation is available by upgrading affected packages to version 3.1.3.
CVE-2025-6547 at a Glance
How to Fix CVE-2025-6547
To remediate this vulnerability, upgrade all affected Pbkdf2 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 pbkdf2@3.1.3
Run the following command in your project directory to verify that all resolved dependencies use the patched release:
npm ls pbkdf2
How to Check if You Are Affected
To determine whether your Node.js application is affected by CVE-2025-6547, inspect your project dependencies using npm:
npm ls pbkdf2
Analyze the terminal output to locate any version of Pbkdf2 in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 3.1.3), your application is affected.
Note: The npm ls pbkdf2 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-20: Improper Input Validation, where the product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. In Pbkdf2, 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-2025-6547 Affected Pbkdf2 Versions
1 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
pbkdf2
|
npm |
≥ 1.0.0
< 3.1.3
|
3.1.3
|
References
Frequently Asked Questions
What is CVE-2025-6547?
Which Pbkdf2 versions are affected?
What version fixes CVE-2025-6547?
Is pbkdf2 affected?
What CWE is associated with CVE-2025-6547?
How can I check npm dependencies for CVE-2025-6547?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-v62p-rq8g-8h59",
"modified" : "2026-02-17T16:39:00Z",
"published" : "2025-06-23T22:42:00Z",
"aliases" : [ "CVE-2025-6547" ],
"summary" : "pbkdf2 silently disregards Uint8Array input, returning static keys",
"details" : "### Summary\n\nOn historic but declared as supported Node.js versions (0.12-2.x), pbkdf2 silently disregards Uint8Array input\n\nThis only affects Node.js <3.0.0, but `pbkdf2` claims to:\n * Support Node.js [>= 0.12](https://github.com/browserify/pbkdf2/blob/v3.1.2/package.json#L62) (and there seems to be ongoing effort in this repo to maintain that)\n * Support `Uint8Array` input (input is typechecked against Uint8Array, and the error message includes e.g. \"Password must be a string, a Buffer, a typed array or a DataView\"\n\n### Details\n\nThe error is in `toBuffer` method\n\nThis vulnerability somehow even made it to tests: https://github.com/browserify/pbkdf2/commit/eb9f97a66ed83836bebc4ff563a1588248708501\nThere, `resultsOld` (where mismatch `results`) are just invalid output generated from empty password/salt instead of the supplied one\n\n### PoC\n\nOn Node.js/io.js < 3.0.0\n\n```console\n> require('pbkdf2').pbkdf2Sync(new Uint8Array([1,2,3]), new Uint8Array([1,3,4]), 1024, 32, 'sha256')\n<Buffer 21 53 cd 5b a5 f0 15 39 2f 68 e2 40 8b 21 ba ca 0e dc 7b 20 d5 45 a4 8a ea b5 95 9f f0 be bf 66>\n\n// But that's just a hash of empty data with empty password:\n> require('pbkdf2').pbkdf2Sync('', '', 1024, 32, 'sha256')\n<Buffer 21 53 cd 5b a5 f0 15 39 2f 68 e2 40 8b 21 ba ca 0e dc 7b 20 d5 45 a4 8a ea b5 95 9f f0 be bf 66>\n\n// Node.js crypto is fine even on that version:\n> require('crypto').pbkdf2Sync(new Uint8Array([1,2,3]), new Uint8Array([1,3,4]), 1024, 32, 'sha256')\n<Buffer 78 10 cc 84 b7 bb 85 cd c8 37 ca 68 da a9 4c 33 db ae c2 3d 5b d4 95 76 da 33 f9 95 ac 51 f4 45>\n\n// Empty hash from Node.js, for comparison\n> require('crypto').pbkdf2Sync('', '', 1024, 32, 'sha256')\n<Buffer 21 53 cd 5b a5 f0 15 39 2f 68 e2 40 8b 21 ba ca 0e dc 7b 20 d5 45 a4 8a ea b5 95 9f f0 be bf 66>\n```\n\n### Impact\n\nStatic hashes being outputted and used as keys/passwords can completely undermine security\nThat said, no one should be using those Node.js versions anywhere now, so I would recommend to just drop them\nThis lib should not pretend to work on those versions while outputting static data though\n\nJust updating to a fixed version is not enough: if anyone was using `pbkdf2` lib (do not confuse with Node.js `crypto.pbkdf2`) or anything depending on it with Node.js/io.js < 3.0.0, recheck where those keys went / how they were used, and take action accordingly",
"severity" : [ {
"type" : "CVSS_V4",
"score" : "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:H/SI:H/SA:H"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "npm",
"name" : "pbkdf2"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "1.0.0"
}, {
"fixed" : "3.1.3"
} ]
} ],
"database_specific" : {
"last_known_affected_version_range" : "<= 3.1.2"
}
} ],
"references" : [ {
"type" : "WEB",
"url" : "https://github.com/browserify/pbkdf2/security/advisories/GHSA-v62p-rq8g-8h59"
}, {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-6547"
}, {
"type" : "WEB",
"url" : "https://github.com/browserify/pbkdf2/commit/e3102a8cd4830a3ac85cd0dd011cc002fdde33bb"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/browserify/pbkdf2"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-20" ],
"severity" : "CRITICAL",
"github_reviewed" : true,
"github_reviewed_at" : "2025-06-23T22:42:00Z",
"nvd_published_at" : "2025-06-23T19:15:25Z"
}
}