Use of Password Hash With Insufficient Computational Effort in the jose library allows an attacker who obtains a password-encrypted private-key export to recover the private key through an offline password-cracking attack.

When jose exports a password-encrypted private key with jose_jwk:to_der/2 (JOSE.JWK.to_der/2), the jose_jwk_der:to_binary/3 function in src/jwk/jose_jwk_der.erl serializes the key as a PKCS#8 EncryptedPrivateKeyInfo using the PBES2 scheme with hardcoded key-derivation parameters: PBKDF2-HMAC-SHA256 with an iteration count of 2048 and an 8-byte (64-bit) random salt. Neither value can be overridden by the caller.

Both values are far below current guidance (OWASP recommends on the order of 600,000 iterations for PBKDF2-HMAC-SHA256, and NIST recommends salts of at least 128 bits), so the key-stretching work factor is roughly 300 times lower than intended and the short salt reduces the cost of precomputation across keys. The symmetric encryption (AES-256-CBC with a 16-byte random IV) is not affected; the weakness is entirely in the derivation strength. An attacker who obtains one of these exported blobs (for example from a backup, configuration repository, object storage, or logs) can mount a cheap offline dictionary or brute-force attack against the export password, and success yields the full private key.

This issue affects jose: from 1.10.0 before 1.11.13.
Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.


Workaround

When exporting a password-encrypted private key with jose_jwk:to_der/2 (JOSE.JWK.to_der/2), use a long, high-entropy passphrase, since the weak key-derivation work factor only meaningfully lowers the cost of cracking guessable passwords. Restrict access to exported EncryptedPrivateKeyInfo blobs and keep them out of backups, repositories, object storage, and logs that an attacker could read.

History

Mon, 26 Oct 2026 20:00:00 +0000

Type Values Removed Values Added
Description Use of Password Hash With Insufficient Computational Effort in the jose library allows an attacker who obtains a password-encrypted private-key export to recover the private key through an offline password-cracking attack. When jose exports a password-encrypted private key with jose_jwk:to_der/2 (JOSE.JWK.to_der/2), the jose_jwk_der:to_binary/3 function in src/jwk/jose_jwk_der.erl serializes the key as a PKCS#8 EncryptedPrivateKeyInfo using the PBES2 scheme with hardcoded key-derivation parameters: PBKDF2-HMAC-SHA256 with an iteration count of 2048 and an 8-byte (64-bit) random salt. Neither value can be overridden by the caller. Both values are far below current guidance (OWASP recommends on the order of 600,000 iterations for PBKDF2-HMAC-SHA256, and NIST recommends salts of at least 128 bits), so the key-stretching work factor is roughly 300 times lower than intended and the short salt reduces the cost of precomputation across keys. The symmetric encryption (AES-256-CBC with a 16-byte random IV) is not affected; the weakness is entirely in the derivation strength. An attacker who obtains one of these exported blobs (for example from a backup, configuration repository, object storage, or logs) can mount a cheap offline dictionary or brute-force attack against the export password, and success yields the full private key. This issue affects jose: from 1.10.0 before 1.11.13.
Title Weak PBKDF2 parameters for password-encrypted private-key export in jose
First Time appeared Potatosalad
Potatosalad jose
Weaknesses CWE-916
CPEs cpe:2.3:a:potatosalad:jose:*:*:*:*:*:*:*:*
Vendors & Products Potatosalad
Potatosalad jose
References
Metrics cvssV4_0

{'score': 7.4, 'vector': 'CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N'}


Projects

Sign in to view the affected projects.

cve-icon MITRE

Status: PUBLISHED

Assigner: EEF

Published:

Updated: 2026-10-26T19:53:35.646Z

Reserved: 2026-07-22T13:58:26.233Z

Link: CVE-2026-65629

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-10-26T20:17:58.647

Modified: 2026-10-26T20:17:58.647

Link: CVE-2026-65629

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses