Link following in yarn - CVE-2019-10773
Published: December 16, 2019 / Updated: July 17, 2020
Vulnerability identifier: #VU30550
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2019-10773
CWE-ID: CWE-59
Exploitation vector: Local access
Exploit availability:
No public exploit available
Vendor: Yarn
Affected software:
yarn
yarn
Detailed vulnerability description
The vulnerability allows a local non-authenticated attacker to execute arbitrary code.
In Yarn before 1.21.1, the package install functionality can be abused to generate arbitrary symlinks on the host filesystem by using specially crafted "bin" keys. Existing files could be overwritten depending on the current user permission set.
How to mitigate CVE-2019-10773
Install update from vendor's website.
Sources
- https://access.redhat.com/errata/RHSA-2020:0475
- https://blog.daniel-ruf.de/critical-design-flaw-npm-pnpm-yarn/
- https://github.com/yarnpkg/yarn/commit/039bafd74b7b1a88a53a54f8fa6fa872615e90e7
- https://github.com/yarnpkg/yarn/issues/7761#issuecomment-565493023
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/3HIZW4NZVV5QY5WWGW2JRP3FHYKZ6ZJ5/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ITY5BC63CCC647DFNUQRQ5AJDKUKUNBI/
- https://snyk.io/vuln/SNYK-JS-YARN-537806,