CVE-2026-81704

Analyzed Analyzed - Analysis Complete

Weak Key Derivation in OpenSSL CryptoService EncryptFile Handler

Publication date: 2026-08-27

Last updated on: 2026-09-03

Assigner: VulnCheck

Description

openssl_encrypt versions before 1.4.9 contain a weak key derivation vulnerability in the D-Bus CryptoService.EncryptFile handler that uses unstretched SHA-256 instead of Argon2id. Attackers can perform offline password guessing against encrypted files roughly six to seven orders of magnitude faster than documented protection by exploiting the missing key stretching and hash rounds.

CVSS Scores

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Meta Information

Published

2026-08-27

Last Modified

2026-09-03

Generated

2026-09-17

AI Q&A

2026-08-27

EPSS Evaluated

2026-09-15

NVD

CVE-2026-81704

EUVD

EUVD-2026-67060

Affected Vendors & Products

Vendor	Product	Version / Range
jahlives	openssl_encrypt	to 1.4.9 (exc)

Helpful Resources

Exploitability

CWE

KEV

CWE ID	Description
CWE-916	The product generates a hash for a password, but it uses a scheme that does not provide a sufficient level of computational effort that would make password cracking attacks infeasible or expensive.

Attack-Flow Graph

Executive Summary

This vulnerability affects openssl_encrypt versions before 1.4.9. It involves a weak key derivation flaw in the D-Bus CryptoService.EncryptFile handler where unstretched SHA-256 is used instead of Argon2id. This allows attackers to perform offline password guessing attacks against encrypted files much faster than intended.

Detection Guidance

To detect this vulnerability, check the version of openssl_encrypt installed on your system. If the version is below 1.4.9, the system is vulnerable. Use commands like 'openssl-encrypt --version' or check package managers (e.g., 'apt list --installed | grep openssl-encrypt' for Debian-based systems).

Additionally, inspect D-Bus CryptoService usage. If the service is active and versions are outdated, the system is at risk. Commands like 'systemctl status dbus' or 'ps aux | grep dbus' may help identify active services.

Impact Analysis

If you use affected versions of openssl_encrypt, encrypted files created via the D-Bus CryptoService are vulnerable. Attackers could guess passwords offline and decrypt files, compromising data confidentiality. Users should update to version 1.4.9 or later and re-encrypt files created with vulnerable versions.

Compliance Impact

This vulnerability likely violates compliance requirements for strong encryption and secure key derivation in GDPR and HIPAA. Using unstretched SHA-256 instead of Argon2id fails to meet standards for sufficient computational effort in password hashing, risking unauthorized data access and regulatory penalties.

Mitigation Strategies

Immediately update openssl_encrypt to version 1.4.9 or later. Use package managers like 'apt upgrade openssl-encrypt' or 'yum update openssl-encrypt' depending on your system.

If using the D-Bus CryptoService, re-encrypt any files created with affected versions using the updated software or CLI tools. Consider disabling the D-Bus service if not required, as it was removed in version 1.5.x.

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