CVE-2021-32842
Because of the file name and destination directory constraints, the arbitrary file creation impact is limited and depends on the use case.
Does this matter?
Lower severity and a low EPSS score (0.90%). Track it; it rarely justifies an emergency change on its own.
Description
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.
- CVSS 3.1
- 5.3 MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
- EPSS
- 0.90% probability · 58th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-22
- Affected
- sharpziplib project/sharpziplib
- Source
- security-advisories@github.com
References
- https://github.com/icsharpcode/SharpZipLib/releases/tag/v1.3.3Release Notes, Third Party Advisory
- https://securitylab.github.com/advisories/GHSL-2021-125-sharpziplib/Exploit, Third Party Advisory
- https://github.com/icsharpcode/SharpZipLib/releases/tag/v1.3.3Release Notes, Third Party Advisory
- https://securitylab.github.com/advisories/GHSL-2021-125-sharpziplib/Exploit, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.