MIT krb5: Insecure temporary file use in send-pr.sh — GLSA 200410-24

The send-pr.sh script, included in the mit-krb5 package, is vulnerable to symlink attacks, potentially allowing a local user to overwrite arbitrary files with the rights of the user running the utility.

Affected packages

app-crypt/mit-krb5 on all architectures
Affected versions <= 1.3.5
Unaffected versions >= 1.3.5-r1
revision >= 1.3.4-r1

Background

MIT krb5 is the free implementation of the Kerberos network authentication protocol written by the Massachusetts Institute of Technology.

Description

The send-pr.sh script creates temporary files in world-writeable directories with predictable names.

Impact

A local attacker could create symbolic links in the temporary files directory, pointing to a valid file somewhere on the filesystem. When send-pr.sh is called, this would result in the file being overwritten with the rights of the user running the utility, which could be the root user.

Workaround

There is no known workaround at this time.

Resolution

All MIT krb5 users should upgrade to the latest version:

 # emerge sync
 
 # emerge -pv ">=app-crypt/mit-krb5-1.3.4-r1"
 # emerge ">=app-crypt/mit-krb5-1.3.4-r1"

References

Release date
October 25, 2004

Latest revision
January 30, 2005: 02

Severity
normal

Exploitable
local

Bugzilla entries