GitHub Advisoryadvisory · NuGet

GHSA-jp7f-grcv-6mjf Partial path traversal in sharpcompress

MEDIUM Published 2021-09-20 Modified 2024-07-08 Official page ↗
Aliases
CVE-2021-39208
Ecosystem
NuGet
Packages
SharpCompress
Severity
Moderate
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
Weaknesses
CWE-22
Reviewed
2021-09-17

Affected packages

• NuGet SharpCompress: < 0.29 → fixed in 0.29

Description

SharpCompress recreates a hierarchy of directories under destinationDirectory if ExtractFullPath is set to true in options. In order to prevent extraction outside the destination directory the destinationFileName path is verified to begin with fullDestinationDirectoryPath. However it is not enforced that fullDestinationDirectoryPath ends with slash: ```csharp public static void WriteEntryToDirectory(IEntry entry, string destinationDirectory, ExtractionOptions? options, Action write) { string destinationFileName; string file = Path.GetFileName(entry.Key); string fullDestinationDirectoryPath = Path.GetFullPath(destinationDirectory); ... throw new ExtractionException("Entry is trying to write a file outside of the destination directory."); } ``` If the destinationDirectory 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. Impact Because of the file name and destination directory constraints the arbitrary file creation impact is limited and depends on the use case.

Related

Alias · CVE (1)

  • CVE-2021-39208 SharpCompress is a fully managed C# library to deal with many compression types and formats. vulnerability

Weakness · CWE (1)

  • CWE-22 Improper Limitation of a Pathname to a Restricted Directory weakness

References