CVE-2026-40261 – Composer
“Two silent weaknesses can quietly open the door to serious damage.”
This patch addresses two high-severity vulnerabilities in Composer, tracked as CVE-2026-40261 and CVE-2026-40176. These issues expose systems to potential compromise through improper handling of dependencies and package operations. CVE-2026-40261 has a CVSS score of 8.8, which is High severity. CVE-2026-40176 has a CVSS score of 7.8, which is also High severity. Both vulnerabilities pose significant risk to application integrity and development pipelines if left unpatched.
No verified exploitation or proof-of-concept code is currently confirmed for these issues. However, the nature of Composer as a dependency manager increases the potential blast radius, as compromised components can propagate risk across multiple projects and environments.
Key Details
- Affected Product
- Getcomposer Composer
- Attack Vector
- Network
- Attack Complexity
- Low
- Privileges Required
- None
- User Interaction
- Required
- CWE Classification
- CWE-20