CVE-2026-9641Network attack vector

Password cracking via weak PBKDF2 defaults

Published Jun 12, 2026 · Updated Jun 12, 2026

Insufficient password-hash strength in Crypt::PBKDF2 before 0.261630 allows attackers to crack exposed hashes with less effort. The module's hash_class and iterations defaults select HMAC-SHA1 and only 1,000 PBKDF2 rounds when applications omit overrides. Exploitation requires access to hashes produced with those defaults; hashes created with explicitly stronger settings do not share this weakness.

CVSS severity5.3
Medium
EPSS probability0.23%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Insufficient password-hash strength in Crypt::PBKDF2 before 0.261630 allows attackers to crack exposed hashes with less effort. The module's hash_class and iterations defaults select HMAC-SHA1 and only 1,000 PBKDF2 rounds when applications omit overrides. Exploitation requires access to hashes produced with those defaults; hashes created with explicitly stronger settings do not share this weakness.

The record

CVE
CVE-2026-9641
Published
Jun 12, 2026
Updated
Jun 12, 2026
Vendor
Andrew Rodland
Product
Crypt::PBKDF2
Classifications
CWE-916, T1110.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 12, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 12, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <0.261630

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Andrew Rodland · Crypt::PBKDF2version=0 <0.261630

Published CVSS scores

5.3CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-916Use of Password Hash With Insufficient Computational Effort
T1110.002Password Cracking

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo