Cybersecurity researchers have identified two information disclosure flaws. These vulnerabilities affect Linux core dump handlers. The handlers are apport and systemd-coredump. They are used in Ubuntu, Red Hat, and Fedora. The Qualys Threat Research Unit found these issues. They are tracked as CVE-2025-5054 and CVE-2025-4598. Both flaws are race condition bugs. They could allow local attackers access. Attackers might obtain sensitive information. They exploit SUID programs to read core dumps. These handlers manage system crash reporting. Core dumps can contain critical data like passwords. Millions of Linux systems worldwide are impacted.
The first vulnerability, CVE-2025-5054, affects Ubuntu’s Apport. It allows leaking information via PID-reuse by attackers. This is achieved by leveraging namespaces effectively. This happens after a privileged process crashes on the system. Canonical stated its impact is restricted. It affects memory confidentiality of SUID executables. The second flaw, CVE-2025-4598, impacts systemd-coredump. An attacker forces an SUID process to crash. They then replace it with a non-SUID binary. This tactic allows access to the original coredump. Sensitive data like /etc/shadow content can be read. Red Hat rated this vulnerability as moderate severity.
Debian systems are not affected by default.
Qualys has developed proof-of-concept (PoC) exploits. These PoCs demonstrate how attackers can operate. They can target the unix_chkpwd process coredump. This allows them to obtain password hashes. These hashes come from the /etc/shadow file. Core dump handlers normally have security measures. They restrict access to root users only. They also store dumps in secure locations. However, these newly found race conditions bypass protections. The potential impact on organizations is severe. Attackers could extract sensitive customer information. This data includes passwords and important encryption keys. This could lead to significant operational downtime.
An immediate mitigation step is available for users.
They can set the suid_dumpable kernel parameter to zero. This command needs to be run as the root user. It effectively disables core dumps for SUID programs. This neutralizes this specific attack vector temporarily. However, it also disables crash analysis for such binaries. Similar security advisories were issued by Amazon Linux. Debian and Gentoo also released related warnings. Qualys also developed mitigation scripts for this issue. Organizations should prioritize updating their core dump handlers. They must also implement recommended temporary mitigations now. Proactive security measures are strongly recommended by experts.
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