SGI Performance Co-Pilot pmpost Symbolic Link Vulnerability
BugTraq ID: 2887
Remote: No
Date Published: 2001-06-18
Relevant URL:
http://www.securityfocus.com/bid/2887
Summary:

Performance Co-Pilot (PCP) is a set of services to support system-level
performance monitoring developed by SGI.  It has traditionally been an
IRIX product, however SGI has made it open source and it is now available
for Linux systems.

One of the utilities that ships with PCP is called 'pmpost'.  It is often
installed setuid root by default.

When 'pmpost' is executed by a user, it logs the command line parameter to
a tempfile ('NOTICES') in the log directory.  The location of the log
directory can be specified via the 'PCP_LOG_DIR' environment variable.

Because environment variables are user supplied, a local user can choose
an arbitrary log directory.  When writing to the 'NOTICES' file in the log
directory, 'pmpost' will follow symbolic links.  Since the data written is
user-supplied (the command-line arguments), it is possible to gain
superuser privileges if 'pmpost' is setuid root.

An attacker may exploit this vulnerabilty by setting the log directory to
one under their control, containing a symbolic link called 'NOTICES'
pointing to a critical system file (such as '/etc/passwd').  The attacker
could overwrite the contents of this file with arbitrary data.

Note: This vulnerability affects both binary versions for IRIX and the
open source distribution of PCP.  S.u.S.E. has made PCP packages available
for their linux distribution.  PCP is not installed as part of S.u.S.E.
Linux by default.  The PCP packages for S.u.S.E. Linux 7.0 do not install
'pmpost' setuid root.  Versions 7.1 and 7.2 do, and are vulnerable if PCP
is installed.

It has been reported that not all versions of PCP for IRIX are vulnerable.
To determine whether you are vulnerable, run this command:

strings /usr/pcp/bin/pmpost | grep PCP_LOG_DIR

If the string 'PCP_LOG_DIR' appears, it is most likely that the version of
'pmpost' installed is vulnerable.

It is not yet known which other Linux vendors may ship with PCP as either
an optional package or installed by default.

W3M Malformed MIME Header Buffer Overflow Vulnerability
BugTraq ID: 2895
Remote: Yes
Date Published: 2001-06-19
Relevant URL:
http://www.securityfocus.com/bid/2895
Summary:

W3M is a pager/text-based WWW browser similar to lynx.

The 'w3m' client program contains a boundary condition error in its
handling of HTTP header fields.

A buffer overflow can occur when a base64-encoded string is received in a
MIME header field.  The string is copied into an internal buffer without
performing bounds checking.  If the string exceeeds approximately 32
characters in length, the extraneous data overwrites neighbouring memory.

If successful, an attacker can have arbitrary code executed with the
privileges of the user running the w3m client.

Juergen Schoenwaelder scotty ntping Buffer Overflow Vulnerability
BugTraq ID: 2911
Remote: No
Date Published: 2001-06-21
Relevant URL:
http://www.securityfocus.com/bid/2911
Summary:

ntping is a component of scotty, a Tcl interpreter used to retrieve status
and configuration information for TCP/IP networks.

The SUID root ntping utility has been found to contain an exploitable
buffer overflow.  When ntping is invoked at the command line, the contents
of argv[0] are copied to an internal variable without bounds checking.
An argument of sufficient length will exceed the size of the destination
buffer and will be copied over neighbouring data on the stack.  If
properly composed, this input can allow a local attacker exploiting this
vulnerability to gain root privilege, leading to a complete system
compromise.

ePerl Foreign Code Execution Vulnerability
BugTraq ID: 2912
Remote: Yes
Date Published: 2001-06-19
Relevant URL:
http://www.securityfocus.com/bid/2912
Summary:

ePerl is a multipurpose Perl filter and interpreter program for Unix
systems.

ePerl provides a preprocessor that allows additional files to be loaded
and processed at runtime, through the use of the 'include' directive.  A
secure variant of the 'include' directive, 'sinclude,' is provided so
external data can be loaded and not processed.  The user-supplied file
path given with these directives can be a relative or absolute path for
the local filesystem, or a fully qualified HTTP URL.

An input validation error exists in this preprocessor.  If a file
referenced by a 'sinclude' directive contains an 'include' directive, the
contents of the file referred to by that directive will be loaded and
executed.

In a situation where the 'sinclude' directive references a file outside of
the script owner's control, it may be possible for the owner of the file
to cause arbitrary code/commands to be executed the next time the script
is run.

cfingerd Utilities Buffer Overflow Vulnerability
BugTraq ID: 2914
Remote: No
Date Published: 2001-06-21
Relevant URL:
http://www.securityfocus.com/bid/2914
Summary:

cfingerd is a secure implementation of the finger daemon.  cfingerd has
been contributed to by many authors, and is maintained by the cfingerd
development team.

A problem with the daemon makes it possible for a local user to gain
elevated privileges.  A buffer overflow in the handling of input by the
daemon makes it possible for a local user to execute arbitrary code, and
gain elevated privileges.  Successful exploitation of this vulnerability
results in root access on the local system.  The problem is in the
handling of input from .nofinger files.

During normal operation, the cfingerd is controlled by inetd.  inetd waits
for incoming finger requests, then calls the daemon to carry out the
request.

The problem involves the validation of input from .nofinger files.  Due to
insufficient input checking by the cfingerd program, it is possible for a
local user to place a string of greater than 80 characters in a .nofinger
file, creating a buffer overflow.  This overflow overwrites stack
variables, including the return address, and can be used to execute code
as root.  Additionally, since the daemon is controlled by inetd, it's
possible to continually retry exploitation of this problem, as if the
daemon dies, it's simply restarted by inetd upon the next finger request.

CFingerD Utilities Format String Vulnerability
BugTraq ID: 2915
Remote: No
Date Published: 2001-06-21
Relevant URL:
http://www.securityfocus.com/bid/2915
Summary:


A problem exists in cfingerd that makes it possible to pass format string
specifiers.  Due to insufficient validation of input in a section of the
util.c file, it's possible to pass arbitrary format strings through the
.nofinger file.

Because there are certain format specifiers which allow writing to memory,
it may be possible for users to create a format string value that will
cause almost arbitrary values to be written to attacker-supplied locations
in memory.

An attacker may be able to use these format specifiers in a maliciously
constructed .nofinger file to cause critical areas of memory to be
corrupted.  An attacker may be able to execute arbitrary code on the host
if a return address or function pointer is overwritten.

cfingerd by default runs as root, and is managed by inetd.  By exploiting
this vulnerability, it's possible for local users to execute arbitrary
code as root, and thus gain root privileges on the local system.

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