CVE-2022-45145 is a critical vulnerability affecting the egg-compile.scm component in CHICKEN Scheme versions prior to 5.3.1. CHICKEN Scheme is a compiler for the Scheme programming language, widely used for scripting and application development. The vulnerability arises during the package installation process, specifically when processing .egg files, which are package archives used by CHICKEN Scheme. An attacker can craft a malicious .egg file containing escape characters that are improperly handled by egg-compile.scm, leading to arbitrary operating system command execution. This means that when a user installs a compromised package, the attacker's commands can be executed on the host system without any authentication or user interaction. The vulnerability is classified under CWE-78 (Improper Neutralization of Special Elements used in an OS Command), indicating that input is not properly sanitized before being passed to system-level commands. The CVSS v3.1 score is 9.8 (critical), reflecting the high impact on confidentiality, integrity, and availability, combined with ease of exploitation (network vector, no privileges or user interaction required). No known exploits in the wild have been reported as of the publication date (December 10, 2022), but the severity and nature of the flaw make it a significant risk for environments using vulnerable CHICKEN Scheme versions. No official patch links were provided in the source, but upgrading to version 5.3.1 or later is implied as the remediation step.

For European organizations, the impact of this vulnerability can be severe, especially for those relying on CHICKEN Scheme for automation, scripting, or application development. Successful exploitation allows attackers to execute arbitrary commands remotely, potentially leading to full system compromise. This can result in data breaches, disruption of critical services, and lateral movement within networks. Confidentiality is at high risk due to possible data exfiltration; integrity can be compromised by unauthorized modification of files or system configurations; availability may be affected if attackers deploy ransomware or disrupt essential processes. Given the lack of authentication and user interaction requirements, attackers can automate exploitation at scale. Organizations in sectors such as finance, manufacturing, research, and government, where CHICKEN Scheme might be used for specialized applications, are particularly vulnerable. The absence of known exploits in the wild does not diminish the urgency, as public disclosure increases the likelihood of weaponization by threat actors.

1. Immediate upgrade to CHICKEN Scheme version 5.3.1 or later where the vulnerability is patched. 2. Implement strict validation and sandboxing of package installations, especially when installing .egg files from untrusted sources. 3. Employ network-level controls to restrict access to package repositories and limit outbound command execution capabilities from build or deployment environments. 4. Monitor logs for unusual command execution patterns or package installation activities. 5. Use application whitelisting to prevent unauthorized execution of unexpected binaries or scripts. 6. Educate developers and system administrators about the risks of installing packages from unverified sources and encourage use of cryptographic verification of package integrity. 7. In environments where immediate upgrade is not feasible, consider isolating CHICKEN Scheme execution within containers or virtual machines with minimal privileges to limit potential damage.