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Test your applicationsUpgrade github.com/snapcore/snapd/overlord/snapshotstate/backend
to version 2.58.1 or higher.
github.com/snapcore/snapd/overlord/snapshotstate/backend is a The snapd and snap tools enable systems to work with .snap files.
Affected versions of this package are vulnerable to Arbitrary File Write via Archive Extraction (Zip Slip). When importing a snapshot (https://snapcraft.io/docs/snapshots), it is possible for a malcious snapshot tar file to traverse a user's system and overwrite any files on the system, through relative paths e.g. "../../"
It is exploited using a specially crafted zip archive, that holds path traversal filenames. When exploited, a filename in a malicious archive is concatenated to the target extraction directory, which results in the final path ending up outside of the target folder. For instance, a zip may hold a file with a "../../file.exe" location and thus break out of the target folder. If an executable or a configuration file is overwritten with a file containing malicious code, the problem can turn into an arbitrary code execution issue quite easily.
The following is an example of a zip archive with one benign file and one malicious file. Extracting the malicous file will result in traversing out of the target folder, ending up in /root/.ssh/
overwriting the authorized_keys
file:
+2018-04-15 22:04:29 ..... 19 19 good.txt
+2018-04-15 22:04:42 ..... 20 20 ../../../../../../root/.ssh/authorized_keys