CVE-1999-0963: High severity FreeBSD FreeBSD vulnerability
FreeBSD mountunion command allows local users to gain root privileges via a symlink attack.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Remove
Remove
freebsd/mount_unionfrom your environment.Uninstall or remove the mount_union command if it is not required. This prevents local users from using the vulnerable utility to escalate privileges via a symlink attack.
- Configuration
Change file permissions or ACLs on the mount_union binary to prevent execution by unprivileged users (for example, restrict to root-only execution) until an official fix is applied.
mount_union command execute_permission = disabled for non-root users - Compensating control
Restrict unprivileged local user access and reduce the number of accounts with shell access. Additionally, apply host-based controls (local ACLs or MAC frameworks) to prevent untrusted users from creating or following symlinks that could be used to exploit mount_union until a vendor patch is available.
Event History
Frequently Asked Questions
What is the severity of CVE-1999-0963?
CVE-1999-0963 has a high severity rating due to its potential to allow local users to gain root privileges.
How do I fix CVE-1999-0963?
To fix CVE-1999-0963, it is recommended to update FreeBSD to the latest stable version that addresses this vulnerability.
Who is affected by CVE-1999-0963?
CVE-1999-0963 affects local users on FreeBSD version 2.2 and earlier.
What type of vulnerability is CVE-1999-0963?
CVE-1999-0963 is a local privilege escalation vulnerability due to a symlink attack.
What is the impact of exploiting CVE-1999-0963?
Exploiting CVE-1999-0963 can lead to complete root access on the affected FreeBSD system.