Multiple CryptX Vulnerabilities Affect Ubuntu 18.04 LTS and Others

Severity: Medium (Score: 57.9)

Sources: Ubuntu, Linuxsecurity

Summary

A series of vulnerabilities in CryptX have been identified, primarily affecting Ubuntu 18.04 LTS. The issues include failure to verify authentication tags during GCM and ChaCha20-Poly1305 decryption (CVE-2018-25099), malformed unicode handling (CVE-2025-40912), and an integer overflow (CVE-2025-40914). Attackers could exploit these vulnerabilities to manipulate ciphertext, leading to data integrity violations, unexpected behavior, or memory corruption. The vulnerabilities are addressed in updates for Ubuntu 18.04 LTS and its derivatives, including Ubuntu 20.04, 22.04, and 24.04 LTS. Users are advised to update their systems to mitigate these risks. The vulnerabilities were disclosed on March 26, 2026, with CVE-2018-25099 published on March 18, 2024, and the others on June 11, 2025. The current status is that patches are available for affected systems. Key Points: • CryptX vulnerabilities affect multiple Ubuntu LTS versions, primarily 18.04. • CVE-2018-25099 allows attackers to bypass authentication checks. • Patches are available for all affected Ubuntu versions.

Key Entities

• DDoS (attack_type)
• CVE-2018-25099 (cve)
• CVE-2025-40912 (cve)
• CVE-2025-40914 (cve)
• Ubuntu (company)