CERT^® Advisory CA-1989-07 Sun RCP vulnerability

A complete revision history is at the end of this file.

A problem has been discovered in the SunOS 4.0.x rcp. If exploited, this problem can allow users of other trusted machines to execute root-privilege commands on a Sun via rcp.

This affects only SunOS 4.0.x systems; 3.5 systems are not affected.

A Sun running 4.0.x rcp can be exploited by any other trusted host listed in /etc/hosts.equiv or /.rhosts. Note that the other machine exploiting this hole does not have to be running Unix; this
vulnerability can be exploited by a PC running PC/NFS, for example.

This bug will be fixed by Sun in version 4.1 (Sun Bug number 1017314), but for now the following workaround is suggested by Sun:

Change the 'nobody' /etc/passwd file entry from

nobody:*:-2:-2::/:

nobody:*:32767:32767:Mismatched NFS ID's:/nonexistant:/nosuchshell

CERT/CC Contact Information

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Phone: +1 412-268-7090 (24-hour hotline)
Fax: +1 412-268-6989
Postal address:

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Software Engineering Institute
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Using encryption

We strongly urge you to encrypt sensitive information sent by email. Our public PGP key is available from

http://www.cert.org/CERT_PGP.key

If you prefer to use DES, please call the CERT hotline for more information.

Getting security information

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http://www.cert.org/

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