CVE-2026-15921
nvm path traversal via a malicious mirror's LTS codename writes outside the alias directory
Node Version Manager (nvm) is a POSIX-compliant shell function for managing multiple node.js versions. In versions 0.32.1 through 0.40.5, nvm ls-remote (and other commands that refresh remote LTS aliases, such as nvm install --lts) parse the node.js mirror's index.tab and use each release's LTS codename field as an alias filename without validating it. A malicious, compromised, or man-in-the-middled mirror can return an LTS codename containing path-traversal sequences such as ../../../.bashrc, causing nvm to write the associated version string to a path outside $NVM_DIR/alias. With the default layout ($NVM_DIR is ~/.nvm), this can create or overwrite files in the user's home directory, including shell startup files, which can lead to code execution in a later shell session. Exploitation requires the victim to use a hostile mirror -- via a compromised mirror or CDN, a network man-in-the-middle, or a maliciously configured NVM_NODEJS_ORG_MIRROR/NVM_IOJS_ORG_MIRROR -- and to run an affected command. Version 0.40.6 validates remote LTS codenames as safe alias filenames and rejects .. path components when writing alias files.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- Active
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
2.1
nvm path traversal via a malicious mirror's LTS codename writes outside the alias directory
Node Version Manager (nvm) is a POSIX-compliant shell function for managing multiple node.js versions. In versions 0.32.1 through 0.40.5, nvm ls-remote (and other commands that refresh remote LTS aliases, such as nvm install --lts) parse the node.js mirror's index.tab and use each release's LTS codename field as an alias filename without validating it. A malicious, compromised, or man-in-the-middled mirror can return an LTS codename containing path-traversal sequences such as ../../../.bashrc, causing nvm to write the associated version string to a path outside $NVM_DIR/alias. With the default layout ($NVM_DIR is ~/.nvm), this can create or overwrite files in the user's home directory, including shell startup files, which can lead to code execution in a later shell session. Exploitation requires the victim to use a hostile mirror -- via a compromised mirror or CDN, a network man-in-the-middle, or a maliciously configured NVM_NODEJS_ORG_MIRROR/NVM_IOJS_ORG_MIRROR -- and to run an affected command. Version 0.40.6 validates remote LTS codenames as safe alias filenames and rejects .. path components when writing alias files.
- Record
CVE-2026-15921- CVSS 4.0
- 2.1 Low
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - CVSS 3.1
- 3.1 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N - Weakness
- CWE-22, CWE-73
- Updated
- 2026-11-02
EUVDEUVD-2026-44818
2.1
Node Version Manager (nvm) is a POSIX-compliant shell function for managing multiple node.js versions. In versions 0.32.1 through 0.40.5, nvm ls-remote (and other commands that refresh remote LTS aliases, such as nvm install --lts) parse the node.js mirror's index.tab and use each release's LTS codename field as an alias filename without validating it. A malicious, compromised, or man-in-the-middled mirror can return an LTS codename containing path-traversal sequences such as ../../../.bashrc, causing nvm to write the associated version string to a path outside $NVM_DIR/alias. With the default layout ($NVM_DIR is ~/.nvm), this can create or overwrite files in the user's home directory, including shell startup files, which can lead to code execution in a later shell session. Exploitation requires the victim to use a hostile mirror -- via a compromised mirror or CDN, a network man-in-the-middle, or a maliciously configured NVM_NODEJS_ORG_MIRROR/NVM_IOJS_ORG_MIRROR -- and to run an affected command. Version 0.40.6 validates remote LTS codenames as safe alias filenames and rejects .. path components when writing alias files.
- Record
EUVD-2026-44818- CVSS 4.0
- 2.1 Low
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - Updated
- 2026-11-02
NVD
2.1
Node Version Manager (nvm) is a POSIX-compliant shell function for managing multiple node.js versions. In versions 0.32.1 through 0.40.5, nvm ls-remote (and other commands that refresh remote LTS aliases, such as nvm install --lts) parse the node.js mirror's index.tab and use each release's LTS codename field as an alias filename without validating it. A malicious, compromised, or man-in-the-middled mirror can return an LTS codename containing path-traversal sequences such as ../../../.bashrc, causing nvm to write the associated version string to a path outside $NVM_DIR/alias. With the default layout ($NVM_DIR is ~/.nvm), this can create or overwrite files in the user's home directory, including shell startup files, which can lead to code execution in a later shell session. Exploitation requires the victim to use a hostile mirror -- via a compromised mirror or CDN, a network man-in-the-middle, or a maliciously configured NVM_NODEJS_ORG_MIRROR/NVM_IOJS_ORG_MIRROR -- and to run an affected command. Version 0.40.6 validates remote LTS codenames as safe alias filenames and rejects .. path components when writing alias files.
- Record
CVE-2026-15921- CVSS 4.0
- 2.1 Low
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 3.1 Low
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N - Weakness
- CWE-22, CWE-73
- Updated
- 2026-11-02
OSV
2.1
nvm path traversal via a malicious mirror's LTS codename writes outside the alias directory
Node Version Manager (nvm) is a POSIX-compliant shell function for managing multiple node.js versions. In versions 0.32.1 through 0.40.5, nvm ls-remote (and other commands that refresh remote LTS aliases, such as nvm install --lts) parse the node.js mirror's index.tab and use each release's LTS codename field as an alias filename without validating it. A malicious, compromised, or man-in-the-middled mirror can return an LTS codename containing path-traversal sequences such as ../../../.bashrc, causing nvm to write the associated version string to a path outside $NVM_DIR/alias. With the default layout ($NVM_DIR is ~/.nvm), this can create or overwrite files in the user's home directory, including shell startup files, which can lead to code execution in a later shell session. Exploitation requires the victim to use a hostile mirror -- via a compromised mirror or CDN, a network man-in-the-middle, or a maliciously configured NVM_NODEJS_ORG_MIRROR/NVM_IOJS_ORG_MIRROR -- and to run an affected command. Version 0.40.6 validates remote LTS codenames as safe alias filenames and rejects .. path components when writing alias files.
- Record
CVE-2026-15921- CVSS 4.0
- 2.1 Low
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-22, CWE-73
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-15921 is a low vulnerability (CVSS 2.1) in Nvm-sh Nvm, published July 15, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.26%, the 18th percentile. No source names a fixed version.