[ CVE-2026-102414 · Published 29 Sep 2026 ]
pbkdf2 rehashes long passwords on every iteration, enabling denial of service
[ Why it matters ]Priority signals
- Public proof-of-concept exploit exists (CISA SSVC)
[ Description ]Official description
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.
[ Fixes ]Fixes and patches
- pbkdf2 3.1.7Fixed version · GitHub Advisories · npm package pbkdf2: upgrade to 3.1.7 or later (affected <= 3.1.6)
[ Packages ]Affected open-source packages
- pbkdf2 npmAffected <= 3.1.6 · fixed in 3.1.7 · GHSA-477h-4r7f-fvrx