5 ms·

Wikileaks releases copies of FinFisher surveillance software

184 points by dpina 12y ago

Strom 12y ago
See yesterday's discussion https://news.ycombinator.com/item?id=8317358 https://news.ycombinator.com/item?id=8317358
markvdb 12y ago
I wonder why they use MD5 hashes and not something more collision attack resistant.
- arturventura 12y ago
  Because it would be very hard to find a collision of a file that behaves exactly like a ZipFile. To make a collision work, you would need to inject the payload into the program, and find a specific blob to put into the zip file, that once compressed and hashed would cause a collision. This isn't computationally efficient.
  - hrjet 12y ago
    I am not familiar with zip file format, but if zip files allow comments or other meta-data (in uncompressed form) then it is an easier path. I suspect even file-names could be an opportunity.
    - fluidcruft 12y ago
      Zip even allows individual file members to be not-compressed. So it's extremely trivial.
  - tlrobinson 12y ago
    This is the type of assumption that can get you in trouble. Zip files can contain uncompressed files.
  - epimenov 12y ago
    That's not true. What people do is take a zip file and then append files to the end till you get desired md5. It would behave like a zip file. See http://www.mscs.dal.ca/~selinger/md5collision/ http://www.mscs.dal.ca/~selinger/md5collision/
  - xwintermutex 12y ago
    One can prepend any data to a zip file and it will still be valid.
- un1xl0ser 12y ago
  Collision resistance is more interesting when hashes are used in cryptographic protocols and large amounts of data can be captured, seen and analyzed. I can't think of a purpose where a collision of a non-malicious sample with a malicious file can be used by an attacker (let alone the same attacker). In addition, there are lots of historical threat data (tactical intelligence) that is based on md5sums. Newer tools support newer checksums, but will more than likely just increase the types of checksums supported, and not deprecate them. Checksums are less and less useful when the malware can be configured, recompiled and re-assembled for a particular target. There are some good discussions on HN more fuzzy detection techniques that can't be evaded by changing inert parts of the payload, but that is orthogonal to using stronger checksums. Indicator of Compromise data including md5sums can be useful for general security, but because a determined attacker will mutate the files it is better suited to more commodity malware.
- Someone1234 12y ago
  Collisions aren't a major risk with MD5 when you also give someone the file size (even approximate). Finding a collision in MD5 is costly, finding a collision in MD5 which is within -+10% of the actual size is extremely costly (technically possible, but maybe not in your lifetime). As to the other reply "because it is zip something something" I disagree. Zip is an extremely good format for crafting fake files which match a checksum. Really any format which can take arbitrary metadata (which is MOST) is pretty easy. I suspect the reason they use MD5 is because everywhere supports it and it is "good enough," particularly with file size. Plus the person downloading them knows the files are malware, so what could the security services do, inject an even more malware-malware that they then expect the user to run?! Seems dumb. You're likely more at risk from day to day applications installers which aren't digitally signed.
  - EthanHeilman 12y ago
    >Finding a collision in MD5 is costly, finding a collision in MD5 which is within -+10% of the actual size is extremely costly (technically possible, but maybe not in your lifetime). MD5 collisions with 10% of the size of the file can be found in seconds on a old laptop computer. I've done it, we assign it as HW in class. Read this http://www.mathstat.dal.ca/~selinger/md5collision/ http://www.mathstat.dal.ca/~selinger/md5collision/ Notice that the two colliding exe are exactly the same file size. These attacks have only gotten better. >Zip is an extremely good format for crafting fake files which match a checksum. Really any format which can take arbitrary metadata (which is MOST) is pretty easy. The example I gave uses windows and linux executables. No zip files in sight. These attacks are from 2009.
    - Someone1234 12y ago
      > Notice that the two colliding exe are exactly the same file size. These attacks have only gotten better. They're also 6, not 200+ KB. They have been specially crafted to be as small as possible to make the problem set as easy as possible. > The example I gave uses windows and linux executables. No zip files in sight. These attacks are from 2009. That's a really strange reply. What is it you think I said..? I said and to quote you quoting me: "'Really any format which can take arbitrary metadata (which is MOST) is pretty easy.'" So why you felt the need to point out that it is an executable not a zip file is uhh strange to say the least...
- EthanHeilman 12y ago
  They should definitely not being using MD5 for anything. Even if the people in this thread saying that finding MD5 collisions is hard were correct, and they aren't, why take the risk? The performance benefits aren't large for MD5 over competing hash functions that don't have know systemic weaknesses and MD5 attacks will only get better. Use SHA256, SHA-3 or MD6 (I like MD6, others may disagree. Disclaimer I worked on proving the differential resistance of MD6).
  - tptacek 12y ago
    MD6 is an idiosyncratic recommendation.
    - EthanHeilman 12y ago
      Fixed.
andy_ppp 12y ago
So, anyone planning to install it?
- DennisP 12y ago
  Now that it's publicly released, it seems like a good idea to install it just to make sure your own systems aren't vulnerable to it.
q3k 12y ago
So, how long until finds RCE bugs in the Proxy, Relay and Master? There is possibly quite a bit of these to be found via Shodan...
billyboar 12y ago
Too shame that they're using so much of money, which is basically tax money of Mongolian people, on surveillance tool when Mongolians living their like hell. shame on them.
JetSpiegel 12y ago
That ggi file is a self-extracting bash script. #!/bin/bash echo "" echo " FInstaller 1.0" echo "-----------------------" export TMPDIR=`mktemp -d /tmp/selfextract.XXXXXX` ARCHIVE=`awk '/^__ARCHIVE_BELOW__/ {print NR + 1; exit 0; }' $0` echo "" echo "Extracting Installation Files..." echo "" tail -n+$ARCHIVE $0 | tar xzv -C $TMPDIR echo "" echo "Launching Installer..." echo "" CDIR=`pwd` echo CDIR echo $CDIR echo TMPDIR echo $TMPDIR cd $TMPDIR ./installer cd $CDIR rm -rf $TMPDIR exit 0 __ARCHIVE_BELOW And then the data.
- JetSpiegel 12y ago
  The installer is an even messier piece of code. #!/bin/bash TOP_INSTALL_DIR=/ echo "Stopping FFRelay" monit stop ffrelay sleep 3 killall -9 -q ffrelay echo "Extracting Software Files..." tar --directory $TOP_INSTALL_DIR -xvf ./*relay*.tar echo "" echo "Running Post-Installation Steps..." SECONDS=1 MAX_SECONDS=10 while [ "$SECONDS" -lt "$MAX_SECONDS" ] do if [ -e "/var/run/ffrelay.pid" ]; then sleep 1 else SECONDS=$MAX_SECONDS fi done echo "Starting FFRelay" monit start ffrelay echo "" echo "FFRelay Installer done." echo "" They should have just used a .deb
D4AHNGM 12y ago
Interestingly, Sophos on OS X immediately identifies the .zip as Malware/Generic-Spyware and blocks access to it: finspy_master.zip: Permission denied

184 points by dpina 12y ago

Strom 12y ago

See yesterday's discussion https://news.ycombinator.com/item?id=8317358 https://news.ycombinator.com/item?id=8317358

markvdb 12y ago

I wonder why they use MD5 hashes and not something more collision attack resistant.

arturventura 12y ago
Because it would be very hard to find a collision of a file that behaves exactly like a ZipFile. To make a collision work, you would need to inject the payload into the program, and find a specific blob to put into the zip file, that once compressed and hashed would cause a collision. This isn't computationally efficient.
- hrjet 12y ago
  I am not familiar with zip file format, but if zip files allow comments or other meta-data (in uncompressed form) then it is an easier path. I suspect even file-names could be an opportunity.
  - fluidcruft 12y ago
    Zip even allows individual file members to be not-compressed. So it's extremely trivial.
- tlrobinson 12y ago
  This is the type of assumption that can get you in trouble. Zip files can contain uncompressed files.
- epimenov 12y ago
  That's not true. What people do is take a zip file and then append files to the end till you get desired md5. It would behave like a zip file. See http://www.mscs.dal.ca/~selinger/md5collision/ http://www.mscs.dal.ca/~selinger/md5collision/
- xwintermutex 12y ago
  One can prepend any data to a zip file and it will still be valid.
un1xl0ser 12y ago
Collision resistance is more interesting when hashes are used in cryptographic protocols and large amounts of data can be captured, seen and analyzed. I can't think of a purpose where a collision of a non-malicious sample with a malicious file can be used by an attacker (let alone the same attacker). In addition, there are lots of historical threat data (tactical intelligence) that is based on md5sums. Newer tools support newer checksums, but will more than likely just increase the types of checksums supported, and not deprecate them. Checksums are less and less useful when the malware can be configured, recompiled and re-assembled for a particular target. There are some good discussions on HN more fuzzy detection techniques that can't be evaded by changing inert parts of the payload, but that is orthogonal to using stronger checksums. Indicator of Compromise data including md5sums can be useful for general security, but because a determined attacker will mutate the files it is better suited to more commodity malware.
Someone1234 12y ago
Collisions aren't a major risk with MD5 when you also give someone the file size (even approximate). Finding a collision in MD5 is costly, finding a collision in MD5 which is within -+10% of the actual size is extremely costly (technically possible, but maybe not in your lifetime). As to the other reply "because it is zip something something" I disagree. Zip is an extremely good format for crafting fake files which match a checksum. Really any format which can take arbitrary metadata (which is MOST) is pretty easy. I suspect the reason they use MD5 is because everywhere supports it and it is "good enough," particularly with file size. Plus the person downloading them knows the files are malware, so what could the security services do, inject an even more malware-malware that they then expect the user to run?! Seems dumb. You're likely more at risk from day to day applications installers which aren't digitally signed.
- EthanHeilman 12y ago
  >Finding a collision in MD5 is costly, finding a collision in MD5 which is within -+10% of the actual size is extremely costly (technically possible, but maybe not in your lifetime). MD5 collisions with 10% of the size of the file can be found in seconds on a old laptop computer. I've done it, we assign it as HW in class. Read this http://www.mathstat.dal.ca/~selinger/md5collision/ http://www.mathstat.dal.ca/~selinger/md5collision/ Notice that the two colliding exe are exactly the same file size. These attacks have only gotten better. >Zip is an extremely good format for crafting fake files which match a checksum. Really any format which can take arbitrary metadata (which is MOST) is pretty easy. The example I gave uses windows and linux executables. No zip files in sight. These attacks are from 2009.
  - Someone1234 12y ago
    > Notice that the two colliding exe are exactly the same file size. These attacks have only gotten better. They're also 6, not 200+ KB. They have been specially crafted to be as small as possible to make the problem set as easy as possible. > The example I gave uses windows and linux executables. No zip files in sight. These attacks are from 2009. That's a really strange reply. What is it you think I said..? I said and to quote you quoting me: "'Really any format which can take arbitrary metadata (which is MOST) is pretty easy.'" So why you felt the need to point out that it is an executable not a zip file is uhh strange to say the least...
EthanHeilman 12y ago
They should definitely not being using MD5 for anything. Even if the people in this thread saying that finding MD5 collisions is hard were correct, and they aren't, why take the risk? The performance benefits aren't large for MD5 over competing hash functions that don't have know systemic weaknesses and MD5 attacks will only get better. Use SHA256, SHA-3 or MD6 (I like MD6, others may disagree. Disclaimer I worked on proving the differential resistance of MD6).
- tptacek 12y ago
  MD6 is an idiosyncratic recommendation.
  - EthanHeilman 12y ago
    Fixed.

andy_ppp 12y ago

So, anyone planning to install it?

DennisP 12y ago
Now that it's publicly released, it seems like a good idea to install it just to make sure your own systems aren't vulnerable to it.

q3k 12y ago

So, how long until finds RCE bugs in the Proxy, Relay and Master? There is possibly quite a bit of these to be found via Shodan...

billyboar 12y ago

Too shame that they're using so much of money, which is basically tax money of Mongolian people, on surveillance tool when Mongolians living their like hell. shame on them.

JetSpiegel 12y ago

That ggi file is a self-extracting bash script. #!/bin/bash echo "" echo " FInstaller 1.0" echo "-----------------------" export TMPDIR=`mktemp -d /tmp/selfextract.XXXXXX` ARCHIVE=`awk '/^__ARCHIVE_BELOW__/ {print NR + 1; exit 0; }' $0` echo "" echo "Extracting Installation Files..." echo "" tail -n+$ARCHIVE $0 | tar xzv -C $TMPDIR echo "" echo "Launching Installer..." echo "" CDIR=`pwd` echo CDIR echo $CDIR echo TMPDIR echo $TMPDIR cd $TMPDIR ./installer cd $CDIR rm -rf $TMPDIR exit 0 __ARCHIVE_BELOW And then the data.

JetSpiegel 12y ago
The installer is an even messier piece of code. #!/bin/bash TOP_INSTALL_DIR=/ echo "Stopping FFRelay" monit stop ffrelay sleep 3 killall -9 -q ffrelay echo "Extracting Software Files..." tar --directory $TOP_INSTALL_DIR -xvf ./*relay*.tar echo "" echo "Running Post-Installation Steps..." SECONDS=1 MAX_SECONDS=10 while [ "$SECONDS" -lt "$MAX_SECONDS" ] do if [ -e "/var/run/ffrelay.pid" ]; then sleep 1 else SECONDS=$MAX_SECONDS fi done echo "Starting FFRelay" monit start ffrelay echo "" echo "FFRelay Installer done." echo "" They should have just used a .deb

D4AHNGM 12y ago

Interestingly, Sophos on OS X immediately identifies the .zip as Malware/Generic-Spyware and blocks access to it: finspy_master.zip: Permission denied