GNU finger Privilege Dropping Vulnerabilities
BID:535
Info
GNU finger Privilege Dropping Vulnerabilities
| Bugtraq ID: | 535 |
| Class: | Access Validation Error |
| CVE: |
CVE-1999-1165 |
| Remote: | No |
| Local: | Yes |
| Published: | Jul 22 1999 12:00AM |
| Updated: | Jul 11 2009 12:56AM |
| Credit: | First posted to BugTraq by Thomas Roessler <[email protected]> on March 17, 1995. Re-posted to BugTraq by Andrew Jone <[email protected]> on March 17, 1999. |
| Vulnerable: |
GNU finger 1.37 |
| Not Vulnerable: | |
Discussion
GNU finger Privilege Dropping Vulnerabilities
There are two vulnerabilities in the GNU finger package downloadable from metalab that have to do with proper privilege dropping. The finger daemon runs as root by default and responds to finger queries for information on the system's users. The first vulnerability allows a malicious user to have an arbitrary program run with gid 0 if the use of .fingerrc is permitted. This is because fingerd drops the uid (0) before gid, leaving itself lacking the permission to drop the gid. The second vulnerability allows an attacker to create a symbolic link from .plan, .forward or .project that fingerd will follow and read with uid 0 (ie. .plan -> /etc/shadow). These vulnerabilities are not new, they were exposed in 1995 on BugTraq and remain unfixed to this day.
There are two vulnerabilities in the GNU finger package downloadable from metalab that have to do with proper privilege dropping. The finger daemon runs as root by default and responds to finger queries for information on the system's users. The first vulnerability allows a malicious user to have an arbitrary program run with gid 0 if the use of .fingerrc is permitted. This is because fingerd drops the uid (0) before gid, leaving itself lacking the permission to drop the gid. The second vulnerability allows an attacker to create a symbolic link from .plan, .forward or .project that fingerd will follow and read with uid 0 (ie. .plan -> /etc/shadow). These vulnerabilities are not new, they were exposed in 1995 on BugTraq and remain unfixed to this day.
Solution / Fix
GNU finger Privilege Dropping Vulnerabilities
Solution:
The only solution is to indefinitely disable GNU fingerd until this is addressed.
Currently the SecurityFocus staff are not aware of any vendor supplied patches for this issue. If you feel we are in error or are aware of more recent information, please mail us at: [email protected].
Solution:
The only solution is to indefinitely disable GNU fingerd until this is addressed.
Currently the SecurityFocus staff are not aware of any vendor supplied patches for this issue. If you feel we are in error or are aware of more recent information, please mail us at: [email protected].
References
GNU finger Privilege Dropping Vulnerabilities
References:
References: