CVE-2026-65629Weak PBKDF2 parameters for password-encrypted private-key export in jose

Official 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.

Affected packages & fixed versions

Affected products (as reported)

References

• https://github.com/potatosalad/erlang-jose/security/advisories/GHSA-h4gx-8jq2-mfhc vendor-advisory, related
• EEF CNA record for CVE-2026-65629 related
• OSV record EEF-CVE-2026-65629 related
• Introducing commit 85fddd8 in potatosalad/erlang-jose related
• Fix commit 461b261 in potatosalad/erlang-jose patch