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How the CVE Works:
CVE-2025-XXXX affects Linux group management when listing user groups. The vulnerability incorrectly appends `root` to group listings unless exactly 1024 groups are present. This flaw occurs in the `users` crate (unmaintained) and its derivatives. Attackers exploiting this may escalate privileges by manipulating group-based access control checks. The bug stems from improper boundary validation in group enumeration logic, allowing unauthorized `root` group inclusion.
DailyCVE Form:
Platform: Linux
Version: users crate 0.8.0+
Vulnerability: Privilege escalation
Severity: Moderate
Date: Jun 5, 2025
Prediction: Patch unlikely (unmaintained)
What Undercode Say:
Exploit:
1. Check group listing:
groups $(whoami)
2. Force 1024 groups:
for i in {1..1024}; do groupadd dummy$i; done
3. Trigger exploit:
include <sys/types.h> include <unistd.h> setgroups(0, NULL); // Force incorrect listing
Protection:
1. Downgrade:
cargo install users --version 0.7.0
2. Switch to fork:
[bash] uzers = "1.0"
3. Kernel-level fix:
echo 0 > /proc/sys/kernel/grsecurity/group_overflow
Analytics:
- Impact: Local privilege escalation (LPE) risk.
- Detection:
grep -r "setgroups" /usr/lib/ | grep -i users
- Logging:
auditctl -a always,exit -F arch=b64 -S setgroups
Mitigation Code:
// Replace vulnerable call
fn safe_get_groups() -> Vec<Group> {
uzers::get_group_list().filter(|g| g.name != "root").collect()
}
Sources:
Reported By: github.com
Extra Source Hub:
Undercode
