CVE-1999-0656
Linux Linux Kernel — CWE-16
EPSS 0.5%
- Published: 1999-01-01T05:00:00.000
- Last modified: 2025-04-03T01:03:51.193
- Vendors: Linux
- Products: Linux Kernel
- CWE: CWE-16
The ugidd RPC interface, by design, allows remote attackers to enumerate valid usernames by specifying arbitrary UIDs that ugidd maps to local user and group names.
Related CVE by CWE
No related CWE found.
Top CVE for Vendor
- CVE-2025-38352 (CVSS 7.4)
- CVE-1999-0524 (no score)
- CVE-2000-0006 (no score)
- CVE-1999-0781 (no score)
- CVE-1999-0414 (no score)
- CVE-1999-1225 (no score)
- CVE-1999-1339 (no score)
- CVE-1999-0782 (no score)
- CVE-1999-0431 (no score)
- CVE-1999-0183 (no score)
Recently Exploited Similar Vulnerabilities
No recent KEV-listed items for this vendor/product.
How to fix CVE-1999-0656
CVE-1999-0656 is a unknown severity vulnerability affecting Linux Linux Kernel.
Description: The ugidd RPC interface, by design, allows remote attackers to enumerate valid usernames by specifying arbitrary UIDs that ugidd maps to local user and group names. Related CVE by CWENo related CWE found.Top CVE for VendorCVE-2025-38352 (CVSS 7.4)CVE-1999-0524 (no score)CVE-2000-0006 (no score)CVE-1999-0781 (no score)CVE-1999-0414 (no score)CVE-1999-1225 (no score)CVE-1999-1339 (no score)CVE-1999-0782 (no score)CVE-1999-0431 (no score)CVE-1999-0183 (no […]
Exploit Difficulty: HARD
⏱️ Time to exploit: > 4 hours
🛠️ Required skills: Advanced security expertise
💰 Public exploits: Rare or not public
How to Fix:
- Check if you're running Linux Kernel
- Update to the latest patched version
- If patching is not immediately possible: restrict network exposure, apply least-privilege access
- Test the fix in a staging environment first
- Review logs for signs of exploitation
- Monitor for IOCs (Indicators of Compromise)
- Enable automatic security updates
- Set up vulnerability monitoring
- Review and harden security configurations
Description: The ugidd RPC interface, by design, allows remote attackers to enumerate valid usernames by specifying arbitrary UIDs that ugidd maps to local user and group names. Related CVE by CWENo related CWE found.Top CVE for VendorCVE-2025-38352 (CVSS 7.4)CVE-1999-0524 (no score)CVE-2000-0006 (no score)CVE-1999-0781 (no score)CVE-1999-0414 (no score)CVE-1999-1225 (no score)CVE-1999-1339 (no score)CVE-1999-0782 (no score)CVE-1999-0431 (no score)CVE-1999-0183 (no […]
Exploit Difficulty: HARD
⏱️ Time to exploit: > 4 hours
🛠️ Required skills: Advanced security expertise
💰 Public exploits: Rare or not public
How to Fix:
1 Identify affected systems
- Check if you're running Linux Kernel
2 Immediate actions
- Update to the latest patched version
- If patching is not immediately possible: restrict network exposure, apply least-privilege access
3 Verification
- Test the fix in a staging environment first
- Review logs for signs of exploitation
- Monitor for IOCs (Indicators of Compromise)
4 Long-term prevention
- Enable automatic security updates
- Set up vulnerability monitoring
- Review and harden security configurations
CWE: CWE-16
Exploit Difficulty Assessment
HARD
Time to Exploit: > 4 hours
Skills Required: Advanced security expertise
Public Exploits: Rare or not public
Vulnerability Timeline
Jan 01, 1999
Vulnerability Published
CVE details first published to NVD database
Apr 03, 2025
Last Modified
CVE details were updated
Oct 31, 2025
Imported to Database
Added to this CVE tracking system
Detection Rules & IOCs
No specific detection rules generated for this vulnerability type.
No explicit mitigation/advisory links found in references.