Skip to main content
← All vulnerabilities
CVE-2021-32842GHSA-MM6G-MMQ6-53FF

Path Traversal in SharpZipLib

Published
Last modified
published
Not listed in CISA KEV
Fix
Fixed in 1.3.3
None on Exploit-DB, Metasploit or GitHub
  • Exploitation: poc
  • Automatable: no
  • Technical impact: partial

Summary

SharpZipLib (or #ziplib) is a Zip, GZip, Tar and BZip2 library. Starting version 1.0.0 and prior to version 1.3.3, a check was added if the destination file is under a destination directory. However, it is not enforced that `_baseDirectory` ends with slash. If the _baseDirectory is not slash terminated like `/home/user/dir` it is possible to create a file with a name thats begins as the destination directory one level up from the 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 fixed this vulnerability.

Timeline

  1. CVE published
  2. CISA SSVC assessment

    Exploitation: poc · Automatable: no · Technical impact: partial

  3. Record last updated

Affected versions

  • icsharpcode sharpziplib

    From 1.3.3 · fixed in 1.3.3; From 1.0.0

  • SharpZipLibNuGet

    From 1.0.0 · fixed in 1.3.3

References 2

securitylab.github.com

GitHub · icsharpcode/SharpZipLib