vulnerability / NVI-00011877 / Revision 2
pbkdf2 rehashes long passwords on every iteration, enabling denial of service
GitHub lists this reviewed advisory for pbkdf2. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
3.7 medium
GitHub source severity; exploitability and local consequence require separate evidence.
As of · GitHub Advisory Database
0.345%
FIRST EPSS model v2026.06.15; exploitation probability over 30 days, percentile 0.28053. Missing scores are unknown.
As of · FIRST EPSS
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
pbkdf2
source listed<= 3.1.6
### Summary This is the same bug as Django had (CVE-2013-1443). ### Details A long password can cause a DoS because it is not using cached HMAC, length limits, or pre-hashing passwords longer than the block size of the hash function as per HMAC spec. This line of code hashes the full password each iteration: https://github.com/browserify/pbkdf2/blob/1c3b1f526b052a29b3b42120c9821895772df7e8/lib/sync.js#L60 Also see https://github.com/browserify/pbkdf2/issues/82 ### PoC The first key will take a lot longer to generate when not using the native code and uses code from `/lib/sync.js` (ie when this if statement is true): https://github.com/browserify/pbkdf2/blob/1c3b1f526b052a29b3b42120c9821895772df7e8/index.js#L33-L37 ```js var pbkdf2 = require('pbkdf2'); var createHash = require('create-hash'); var pw = ".".repeat(1048576); // 1 MiB var t0 = performance.now(); var key1 = pbkdf2.pbkdf2Sync(pw, "salt", 1000, 32, "sha256"); var t1 = performance.now(); pw = createHash('sha256').update(pw).digest(); // HMAC specification for keys larger than block size var key2 = pbkdf2.pbkdf2Sync(pw, "salt", 1000, 32, "sha256"); var t2 = performance.now(); console.log("First took: " + (t1 - t0)); c
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. FIRST EPSS
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-477h-4r7f-fvrx ↗
GitHub Advisory Database · vendor advisory
Observed . GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.
- CVE-2026-102414 ↗
FIRST EPSS · official catalog
Observed . FIRST EPSS; probability of exploitation in the next 30 days, not local compromise. Dataset date/model retained; FIRST services terms apply.
Public revision history
Only published revisions appear here. Routine fetches do not create a material-change event.
- Revision 2 ·
Dated EPSS estimate updated; this is not a new disclosure or proof of exploitation.
- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.