CVE-2026-15921
nvm path traversal via a malicious mirror's LTS codename writes outside the alias directory
Description
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.
INFO
Published Date :
July 15, 2026, 10:16 p.m.
Last Modified :
July 15, 2026, 10:16 p.m.
Remotely Exploit :
Yes !
Source :
7ffcee3d-2c14-4c3e-b844-86c6a321a158
Affected Products
The following products are affected by CVE-2026-15921
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | LOW | 7ffcee3d-2c14-4c3e-b844-86c6a321a158 | ||||
| CVSS 4.0 | LOW | 7ffcee3d-2c14-4c3e-b844-86c6a321a158 | ||||
| CVSS 4.0 | LOW | 7ffcee3d-2c14-4c3e-b844-86c6a321a158 |
Solution
- Update Node Version Manager to version 0.40.6 or later.
- Ensure NVM uses trusted mirrors for remote version information.
- Avoid using untrusted or user-provided mirror configurations.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-15921.
| URL | Resource |
|---|---|
| https://github.com/nvm-sh/nvm/commit/9275c5badda1d9d0cdad6f34598a111033eadb42 | |
| https://github.com/nvm-sh/nvm/security/advisories/GHSA-4ghp-wxpw-rhpg |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-15921 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-15921
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-15921 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-15921 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by 7ffcee3d-2c14-4c3e-b844-86c6a321a158
Jul. 15, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://github.com/nvm-sh/nvm', 'vendor': 'nvm-sh', 'product': 'nvm', 'versions': [{'status': 'affected', 'version': '0.32.1', 'lessThan': '0.40.6', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}] Added Description 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. Added CVSS V4.0 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 Added CVSS V3.1 AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N Added CWE CWE-22 Added CWE CWE-73 Added Reference https://github.com/nvm-sh/nvm/commit/9275c5badda1d9d0cdad6f34598a111033eadb42 Added Reference https://github.com/nvm-sh/nvm/security/advisories/GHSA-4ghp-wxpw-rhpg