8.6 High
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
4.4 Medium
CVSS2
Access Vector
LOCAL
Access Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
AV:L/AC:M/Au:N/C:P/I:P/A:P
0.001 Low
EPSS
Percentile
25.0%
Arbitrary File Creation, Arbitrary File Overwrite, Arbitrary Code Execution
node-tar aims to guarantee that any file whose location would be outside of the extraction target directory is not extracted. This is, in part, accomplished by sanitizing absolute paths of entries within the archive, skipping archive entries that contain ..
path portions, and resolving the sanitized paths against the extraction target directory.
This logic was insufficient on Windows systems when extracting tar files that contained a path that was not an absolute path, but specified a drive letter different from the extraction target, such as C:some\path
. If the drive letter does not match the extraction target, for example D:\extraction\dir
, then the result of path.resolve(extractionDirectory, entryPath)
would resolve against the current working directory on the C:
drive, rather than the extraction target directory.
Additionally, a ..
portion of the path could occur immediately after the drive letter, such as C:../foo
, and was not properly sanitized by the logic that checked for ..
within the normalized and split portions of the path.
This only affects users of node-tar
on Windows systems.
4.4.18 || 5.0.10 || 6.1.9
There is no reasonable way to work around this issue without performing the same path normalization procedures that node-tar now does.
Users are encouraged to upgrade to the latest patched versions of node-tar, rather than attempt to sanitize paths themselves.
The fixed versions strip path roots from all paths prior to being resolved against the extraction target folder, even if such paths are not โabsoluteโ.
Additionally, a path starting with a drive letter and then two dots, like c:../
, would bypass the check for ..
path portions. This is checked properly in the patched versions.
Finally, a defense in depth check is added, such that if the entry.absolute
is outside of the extraction taret, and we are not in preservePaths:true mode, a warning is raised on that entry, and it is skipped. Currently, it is believed that this check is redundant, but it did catch some oversights in development.
cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
github.com/advisories/GHSA-5955-9wpr-37jh
github.com/isaacs/node-tar/commit/52b09e309bcae0c741a7eb79a17ef36e7828b946
github.com/isaacs/node-tar/commit/82eac952f7c10765969ed464e549375854b26edc
github.com/isaacs/node-tar/commit/875a37e3ec031186fc6599f6807341f56c584598
github.com/npm/node-tar/security/advisories/GHSA-5955-9wpr-37jh
nvd.nist.gov/vuln/detail/CVE-2021-37713
www.npmjs.com/package/tar
www.oracle.com/security-alerts/cpuoct2021.html
8.6 High
CVSS3
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
4.4 Medium
CVSS2
Access Vector
LOCAL
Access Complexity
MEDIUM
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
AV:L/AC:M/Au:N/C:P/I:P/A:P
0.001 Low
EPSS
Percentile
25.0%