FreeBSD VuXML: Documenting security issues in FreeBSD and the FreeBSD Ports Collection

cvsbug -- race condition

Affected packages
cvs+ipv6 < 1.11.17_1
Affected systems
5.4 <= FreeBSD < 5.4_7
5.3 <= FreeBSD < 5.3_22
4.11 <= FreeBSD < 4.11_12
4.10 <= FreeBSD < 4.10_18

Details

VuXML ID c5c17ead-8f23-11da-8c1d-000e0c2e438a
Discovery 2005-09-07
Entry 2006-01-27
Modified 2006-11-08

Problem description

A temporary file is created, used, deleted, and then re-created with the same name. This creates a window during which an attacker could replace the file with a link to another file. While cvsbug(1) is based on the send-pr(1) utility, this problem does not exist in the version of send-pr(1) distributed with FreeBSD.
In FreeBSD 4.10 and 5.3, some additional problems exist concerning temporary file usage in both cvsbug(1) and send-pr(1).

Impact

A local attacker could cause data to be written to any file to which the user running cvsbug(1) (or send-pr(1) in FreeBSD 4.10 and 5.3) has write access. This may cause damage in itself (e.g., by destroying important system files or documents) or may be used to obtain elevated privileges.

Workaround

Do not use the cvsbug(1) utility on any system with untrusted users.
Do not use the send-pr(1) utility on a FreeBSD 4.10 or 5.3 system with untrusted users.

References

CVE Name CAN-2005-2693
FreeBSD Advisory SA-05:20.cvsbug