CVEvulnerability
CVE-2021-21300
7.5 HIGH
Official page ↗
- Status
- Modified
- Published
- 2021-03-09
- Last modified
- 2026-06-17
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 8.0 HIGH — CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N
- CVSS 3.1 ([email protected])
- 7.5 HIGH — CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
- CVSS 2.0 ([email protected])
- 5.1 MEDIUM — AV:N/AC:H/Au:N/C:P/I:P/A:P
- Weaknesses
- CWE-59
Description
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.
Affected configurations
• git-scm git (<= 2.14.2)
• git-scm git (>= 2.17.0 < 2.17.6)
• git-scm git (>= 2.18.0 < 2.18.5)
• git-scm git (>= 2.19.0 < 2.19.6)
• git-scm git (>= 2.20.0 < 2.20.5)
• git-scm git (>= 2.21.0 < 2.21.4)
• git-scm git (>= 2.22.0 < 2.22.5)
• git-scm git (>= 2.23.0 < 2.23.4)
• git-scm git (>= 2.24.0 < 2.24.4)
• git-scm git (>= 2.25.0 < 2.25.5)
• git-scm git (>= 2.26.0 < 2.26.3)
• git-scm git (>= 2.29.0 < 2.29.3)
• git-scm git (>= 2.30.0 < 2.30.2)
• git-scm git 2.27.0
• git-scm git 2.28.0
• fedoraproject fedora 32
• fedoraproject fedora 33
• fedoraproject fedora 34
• apple xcode (< 12.5)
• debian debian linux 10.0
Related
Weakness · CWE (1)
- CWE-59 Improper Link Resolution Before File Access weakness
References
- http://packetstormsecurity.com/files/163978/Git-LFS-Clone-Command-Execution.html Exploit, Third Party Advisory, VDB Entry
- http://seclists.org/fulldisclosure/2021/Apr/60 Mailing List, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2021/03/09/3 Exploit, Mailing List, Third Party Advisory
- https://git-scm.com/docs/git-config#Documentation/git-config.txt-coresymlinks Vendor Advisory
- https://git-scm.com/docs/gitattributes#_filter Vendor Advisory
- https://github.com/git/git/commit/684dd4c2b414bcf648505e74498a608f28de4592 Patch, Third Party Advisory
- https://github.com/git/git/security/advisories/GHSA-8prw-h3cq-mghm Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2022/10/msg00014.html Mailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BBPNGLQSYJHLZZ37BO42YY6S5OTIF4L4/ lists.fedoraproject.org
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LCLJJLKKMS5WRFO6C475AOUZTWQLIARX/ lists.fedoraproject.org
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LMXX2POK5X576BSDWSXGU7EIK6I72ERU/ lists.fedoraproject.org
- https://lore.kernel.org/git/xmqqim6019yd.fsf%40gitster.c.googlers.com/ lore.kernel.org
- https://security.gentoo.org/glsa/202104-01 Third Party Advisory
- https://support.apple.com/kb/HT212320 Third Party Advisory
- http://packetstormsecurity.com/files/163978/Git-LFS-Clone-Command-Execution.html Exploit, Third Party Advisory, VDB Entry
- http://seclists.org/fulldisclosure/2021/Apr/60 Mailing List, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2021/03/09/3 Exploit, Mailing List, Third Party Advisory
- https://git-scm.com/docs/git-config#Documentation/git-config.txt-coresymlinks Vendor Advisory
- https://git-scm.com/docs/gitattributes#_filter Vendor Advisory
- https://github.com/git/git/commit/684dd4c2b414bcf648505e74498a608f28de4592 Patch, Third Party Advisory
- https://github.com/git/git/security/advisories/GHSA-8prw-h3cq-mghm Third Party Advisory
- https://lists.debian.org/debian-lts-announce/2022/10/msg00014.html Mailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BBPNGLQSYJHLZZ37BO42YY6S5OTIF4L4/ lists.fedoraproject.org
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LCLJJLKKMS5WRFO6C475AOUZTWQLIARX/ lists.fedoraproject.org
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LMXX2POK5X576BSDWSXGU7EIK6I72ERU/ lists.fedoraproject.org
- https://lore.kernel.org/git/xmqqim6019yd.fsf%40gitster.c.googlers.com/ lore.kernel.org
- https://security.gentoo.org/glsa/202104-01 Third Party Advisory
- https://support.apple.com/kb/HT212320 Third Party Advisory