CVE-2023-24626 describes a vulnerability in GNU Screen, specifically in the socket.c component for versions up to 4.9.0. When installed with setuid or setgid permissions, which is common in distributions such as Arch Linux and FreeBSD, this vulnerability allows local users to send a privileged SIGHUP signal to any process ID (PID). This can lead to a denial of service or disruption of the affected process.
The CVSS score for this vulnerability is 6.5, classifying it as medium severity. The score reflects that the attack vector is local, requiring low complexity, low privileges, and no user interaction. The potential impact is significant, particularly concerning availability, as it can cause process disruptions.
Risk to organizations includes potential service disruptions and impacts on application availability, particularly for those relying on GNU Screen in multi-user environments. Organizations should prioritize addressing this vulnerability to mitigate risks.
Given the medium severity of this CVE, organizations should schedule remediation within their patch management cycle. It is crucial to stay informed about updates and patches provided by the vendor to ensure that all instances are secured.
Vulnerability Details
The vulnerability is classified under CWE-732, which relates to incorrect permission assignment. Specifically, the affected version of GNU Screen (up to 4.9.0) allows local users to leverage the setuid or setgid bit to send privileged signals, thus affecting the availability of processes.
This vulnerability was published on April 8, 2023. Organizations using affected versions are urged to review their configurations and permissions to ensure they are not exposing themselves to unnecessary risks.
Technical Analysis
The root cause of CVE-2023-24626 lies in the misuse of setuid and setgid permissions, which enable local users to gain elevated privileges over process management. The attack vector is local, indicating that an attacker must have local access to exploit this vulnerability. The complexity of the attack is low, as it does not require sophisticated methods or extensive knowledge.
Exploitation of this vulnerability does not require user interaction, making it even more critical. The confidentiality impact is none, as the vulnerability does not expose sensitive information, but it has a high availability impact, potentially disrupting essential services.
Risk & Impact Analysis
Organizations utilizing GNU Screen in their environments should assess the real-world risk associated with this vulnerability. The ability for a local user to disrupt processes can lead to significant operational impacts, especially in environments where uptime is critical.
The blast radius of this vulnerability is potentially extensive, affecting any processes that rely on GNU Screen. This could range from user sessions to important background services.
Given the CVSS score of 6.5, organizations should prioritize patching this vulnerability in their upcoming patch cycles. Delaying remediation can lead to exploit scenarios that could have been easily mitigated.
Exploitation Status
Signal | Status |
|---|---|
Known Exploit | Yes |
Public PoC | No |
Actively Exploited | No |
Ransomware Use | No |
Affected Versions
All versions of GNU Screen up to and including 4.9.0 are affected by this vulnerability. Organizations should ensure they upgrade to versions that have addressed this issue.
Mitigation & Remediation
To mitigate this vulnerability, organizations should upgrade to the latest patched version of GNU Screen. If an immediate upgrade is not possible, consider applying workarounds such as modifying the permissions of the affected binaries or restricting access to local users.
Organizations may also implement configuration hardening strategies to limit the impact of local users having elevated privileges. Regular security assessments and continuous monitoring should be part of the security posture.
For comprehensive security assessments, organizations should consider integrating penetration testing into their security strategy.
Detection Guidance
Organizations should monitor logs for unusual process terminations or unexpected SIGHUP signals. Behavioral anomalies in process management can indicate attempts to exploit this vulnerability.
Network signatures that identify unauthorized use of local privilege escalation techniques should also be implemented.
AppSecure Threat Intelligence Insight
The long-term significance of CVE-2023-24626 lies in its illustration of the risks associated with improper permission assignments in applications. This vulnerability highlights the importance of adhering to the principle of least privilege in system configurations.
Organizations should learn from this incident to reinforce their security policies, ensuring that all software components are regularly reviewed for vulnerabilities and patched accordingly.
For further reading on security best practices, organizations may find value in exploring penetration testing methodology. Additionally, understanding vulnerability management programs can significantly enhance their defensive strategies.
Lastly, organizations should consider the resources available in the field of API security testing to bolster their overall security posture.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
.webp)