QID 352257

Date Published: 2021-04-05

QID 352257: Amazon Linux Security Advisory for git: ALAS2-2021-1621

<DIV> Issue Overview:

Git is an open-source distributed revision control system. In affected versions of Git a specially crafted repository that contains symbolic links as well as files using a clean/smudge filter such as Git LFS, may cause just-checked out script to be executed while cloning onto a case-insensitive file system such as NTFS, HFS+ or APFS (i.e. the default file systems on Windows and macOS). Note that clean/smudge filters have to be configured for that. Git for Windows configures Git LFS by default, and is therefore vulnerable. The problem has been patched in the versions published on Tuesday, March 9th, 2021. As a workaound, if symbolic link support is disabled in Git (e.g. via `git config --global core.symlinks false`), the described attack won't work. Likewise, if no clean/smudge filters such as Git LFS are configured globally (i.e. _before_ cloning), the attack is foiled. As always, it is best to avoid cloning repositories from untrusted sources. The earliest impacted version is 2.14.2. The fix versions are: 2.30.1, 2.29.3, 2.28.1, 2.27.1, 2.26.3, 2.25.5, 2.24.4, 2.23.4, 2.22.5, 2.21.4, 2.20.5, 2.19.6, 2.18.5, 2.17.62.17.6. (CVE-2021-21300 )

</DIV>

Allows unauthorized disclosure of information; allows unauthorized modification; allows disruption of service.

  • CVSS V3 rated as High - 7.5 severity.
  • CVSS V2 rated as Medium - 5.1 severity.
  • Solution
    Please refer to Amazon advisory ALAS-2021-1621 for affected packages and patching details, or update with your package manager.
    Vendor References

    CVEs related to QID 352257

    Software Advisories
    Advisory ID Software Component Link
    ALAS-2021-1621 Amazon Linux 2 git (2.23.4-1.amzn2.0.1) on aarch64 URL Logo alas.aws.amazon.com/AL2/ALAS-2021-1621.html
    ALAS-2021-1621 Amazon Linux 2 git (2.23.4-1.amzn2.0.1) on i686 URL Logo alas.aws.amazon.com/AL2/ALAS-2021-1621.html
    ALAS-2021-1621 Amazon Linux 2 git (2.23.4-1.amzn2.0.1) on noarch URL Logo alas.aws.amazon.com/AL2/ALAS-2021-1621.html
    ALAS-2021-1621 Amazon Linux 2 git (2.23.4-1.amzn2.0.1) on src URL Logo alas.aws.amazon.com/AL2/ALAS-2021-1621.html
    ALAS-2021-1621 Amazon Linux 2 git (2.23.4-1.amzn2.0.1) on x86_64 URL Logo alas.aws.amazon.com/AL2/ALAS-2021-1621.html