CVE-2020-26312 GHSL-2020-254: Arbitrary file read and/or write in dotmesh

2024-05-1420:22:04

CWE-125

CWE-787

GitHub_M

www.cve.org

cve-2020-26312

ghsl-2020-254

dotmesh

symbolic links

unpacking routine

arbitrary file write

8.1 High

CVSS3

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

LOW

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

HIGH

Integrity Impact

HIGH

Availability Impact

NONE

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N

7.8 High

AI Score

Confidence

High

0.0004 Low

EPSS

Percentile

9.1%

JSON

Dotmesh is a git-like command-line interface for capturing, organizing and sharing application states. In versions 0.8.1 and prior, the unsafe handling of symbolic links in an unpacking routine may
enable attackers to read and/or write to arbitrary locations outside the
designated target folder. The routine untarFile attempts to guard against creating symbolic links that point outside the directory a tar archive is extracted to. However, a malicious tarball first linking subdir/parent to .. (allowed, because subdir/.. falls within the archive root) and then linking subdir/parent/escapes to .. results in a symbolic link pointing to the tarball’s parent directory, contrary to the routine’s goals. This issue may lead to arbitrary file write (with same permissions as the program running the unpack operation) if the attacker can control the archive file. Additionally, if the attacker has read access to the unpacked files, they may be able to read arbitrary system files the parent process has permissions to read. As of time of publication, no patch for this issue is available.

CNA Affected

[
  {
    "defaultStatus": "unaffected",
    "packageName": "dotmesh",
    "product": "dotmesh",
    "repo": "https://github.com/dotmesh-io/dotmesh",
    "vendor": "dotmesh-io",
    "versions": [
      {
        "lessThanOrEqual": "0.8.1",
        "status": "affected",
        "version": "0",
        "versionType": "custom"
      }
    ]
  }
]