CVE-2021-32841

Summary

SharpZipLib (or #ziplib) is a Zip, GZip, Tar and BZip2 library. Starting version 1.3.0 and prior to version 1.3.3, a check was added if the destination file is under destination directory. However, it is not enforced that destDir ends with slash. If the destDir is not slash terminated like /home/user/dir it is possible to create a file with a name thats begins with the destination directory, i.e. /home/user/dir.sh. Because of the file name and destination directory constraints, the arbitrary file creation impact is limited and depends on the use case. Version 1.3.3 contains a patch for this vulnerability.

Affected Software

VendorProductVersion RangeStatus
icsharpcodesharpziplib1.3.3 < 1.3.3affected
icsharpcodesharpziplib1.3.0 < 1.3.0*affected

Weaknesses

  • CWE-22: CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

ADP Enrichment

CVE Program Container

Additional References

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: poc
    • Automatable: no
    • Technical Impact: partial

References