Solaris /usr/lib/exrecover buffer overflow

[Pablo Sor <psor () AFIP GOV AR>]

Hi,

The /usr/lib/exrecover contains a buffer overflow
(this command is suid in Solaris 2.4/5/6)
The problem occurs when it gets the second argument, it accepts the
argument without checking out its lenght and this causes the problem.
The overflow seems to be in the heap space.

$ /usr/lib/exrecover hola `perl -e 'printf "A"x50000'`
Segmentation Fault (core dumped)

$ gdb /usr/lib/exrecover --core=core

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This GDB was configured as "sparc-sun-solaris2.6"...
(no debugging symbols found)...
Core was generated by `/usr/lib/exrecover hola
AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA'.
Program terminated with signal 11, Segmentation Fault.
Reading symbols from /usr/lib/libmapmalloc.so.1...
(no debugging symbols found)...done.
Reading symbols from /usr/lib/libc.so.1...(no debugging symbols
found)...done.
Reading symbols from /usr/lib/libdl.so.1...(no debugging symbols
found)...done.
Reading symbols from /usr/platform/SUNW,Ultra-5_10/lib/libc_psr.so.1...
(no debugging symbols found)...done.
#0  0xef6a44d8 in strcpy ()


Pablo Sor
psor () afip gov ar