pbkdf2 rehashes long passwords on every iteration, enabling denial of service
pbkdf2 through 3.1.6 re-hashes passwords longer than the digest's block size on every iteration in its JavaScript fallback (lib/sync.js). A password longer than the block size (64 bytes, or 128 bytes for sha384 and sha512) is passed to HMAC as the key on every iteration, and HMAC hashes such keys in full each time. Cost is therefore O(iterations × password length), and a long password can block the event loop. The fallback is used by pbkdf2Sync and pbkdf2 on Node.js before 0.12, on Bun (1.0.0 through 1.1.34, and 1.2.6 and later), and on Deno 2.9.0 and later, because their native pbkdf2Sync fails the library's feature check. It is also used when lib/sync.js is imported directly. Node.js 0.12 and later, and browser builds (which use lib/sync-browser.js), are not affected. Applications that enforce a reasonable maximum password length are not meaningfully affected.
- Products
- Not specified
- Affected versions
- Not specified
- Fixed versions
- Not specified
- CVEs
- CVE-2026-102414
- Confirmed fixed CVEs
- Not specified
- Updated in this feed
- 4 Nov 2026, 21:14 UTC · Revision 1
Source evidence
pbkdf2 rehashes long passwords on every iteration, enabling denial of service
core-osv · Original sourcePublished 29 Sept 2026, 03:42 UTC
pbkdf2 through 3.1.6 re-hashes passwords longer than the digest's block size on every iteration in its JavaScript fallback (lib/sync.js). A password longer than the block size (64 bytes, or 128 bytes for sha384 and sha512) is passed to HMAC as the key on every iteration, and HMAC hashes such keys in full each time. Cost is therefore O(iterations × password length), and a long password can block the event loop. The fallback is used by pbkdf2Sync and pbkdf2 on Node.js before 0.12, on Bun (1.0.0 through 1.1.34, and 1.2.6 and later), and on Deno 2.9.0 and later, because their native pbkdf2Sync fails the library's feature check. It is also used when lib/sync.js is imported directly. Node.js 0.12 and later, and browser builds (which use lib/sync-browser.js), are not affected. Applications that enforce a reasonable maximum password length are not meaningfully affected.
osv:CVE-2026-102414
Complete source record
{
"id": "e0f37781729ed22d22df304a9d5a30a517b2dc53fff246d9e08498beaf4c1328",
"url": "https://osv.dev/vulnerability/CVE-2026-102414",
"method": "structured",
"payload": {
"kind": "advisory",
"title": "pbkdf2 rehashes long passwords on every iteration, enabling denial of service",
"summary": "pbkdf2 through 3.1.6 re-hashes passwords longer than the digest's block size on every iteration in its JavaScript fallback (lib/sync.js). A password longer than the block size (64 bytes, or 128 bytes for sha384 and sha512) is passed to HMAC as the key on every iteration, and HMAC hashes such keys in full each time. Cost is therefore O(iterations × password length), and a long password can block the event loop. The fallback is used by pbkdf2Sync and pbkdf2 on Node.js before 0.12, on Bun (1.0.0 through 1.1.34, and 1.2.6 and later), and on Deno 2.9.0 and later, because their native pbkdf2Sync fails the library's feature check. It is also used when lib/sync.js is imported directly. Node.js 0.12 and later, and browser builds (which use lib/sync-browser.js), are not affected. Applications that enforce a reasonable maximum password length are not meaningfully affected.",
"evidence": "osv:CVE-2026-102414",
"products": [],
"severity": "medium",
"structured": {
"id": "CVE-2026-102414",
"aliases": [
"CVE-2026-102414",
"GHSA-477h-4r7f-fvrx"
],
"metrics": [
{
"type": "CVSS_V4",
"score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N"
}
],
"affected": [
{
"ranges": [
{
"repo": "https://github.com/browserify/pbkdf2",
"type": "GIT",
"events": [
{
"introduced": "0"
},
{
"fixed": "493d8d8"
}
],
"database_specific": {
"extracted_events": [
{
"range": [
{
"introduced": "0"
},
{
"last_affected": "3.1.6"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StandardRange"
},
{
"range": [
{
"fixed": "493d8d8"
}
],
"source": "REFERENCES_COMMIT"
}
]
}
}
],
"database_specific": {
"source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-102414.json"
}
}
],
"modified": "2026-10-28T02:30:39.635933960Z",
"provider": "osv",
"references": [
"https://www.npmjs.com",
"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/102xxx/CVE-2026-102414.json",
"https://github.com/browserify/pbkdf2/security/advisories/GHSA-477h-4r7f-fvrx",
"https://nvd.nist.gov/vuln/detail/CVE-2026-102414",
"https://github.com/browserify/pbkdf2/issues/82",
"https://github.com/browserify/pbkdf2/commit/493d8d8",
"https://github.com/browserify/pbkdf2"
],
"provider_metadata": {
"cwe_ids": [
"CWE-400"
],
"cna_assigner": "harborist",
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/102xxx/CVE-2026-102414.json"
}
},
"related_cves": [
{
"value": "CVE-2026-102414",
"evidence": "/id"
}
],
"security_relevant": true,
"severity_evidence": "/severity/0/score"
},
"source_id": "core-osv",
"document_id": 507104,
"published_at": "2026-09-29T03:42:04.95+00:00"
}