nvm resolves a requested version or alias by treating it as a filename under $NVM_DIR/alias. Before 0.40.8, nvm_alias() concatenated the requested name onto that directory and read the result with no containment check, so a name containing a `..` component escaped the alias directory; under the default layout an alias such as `../../.npmrc` resolves to a file in the user's home directory. nvm_print_alias_file() then emits every non-comment, non-empty line of whatever was opened. A version string taken from an untrusted .nvmrc reaches this path, so a developer who runs `nvm use`, `nvm install`, or `nvm which` inside an attacker-supplied repository discloses the first non-comment line of an arbitrary file readable by that user, in the resulting "is not yet installed" error message. A user-supplied `nvm alias <traversing-name>` discloses every non-comment line of the target file. There is no integrity or availability impact, and no command execution on this path.
https://github.com/nvm-sh/nvm/security/advisories/GHSA-8grh-q73j-ffrc
Published: 2026-09-21
Updated: 2026-09-22
Base Score: 4.9
Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:N/A:N
Severity: Medium
Base Score: 5.5
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Severity: Medium
Base Score: 6.7
Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
Severity: Medium
EPSS: 0.00294