CVE-2026-118905: nvm_ls lets an untrusted version string inject sed commands, executing arbitrary commands with GNU sed
Noroxi assessment
Priority: Monitor (action score 28/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 0.13% (FIRST EPSS).
- Someone with local access to the system can trigger it. No account or password is required. No special conditions are required; it is repeatable.
- Fixed version: nvm-sh nvm 0.40.6.
Low priority for now. Upgrade to nvm-sh nvm 0.40.6 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
Node Version Manager (nvm) is a POSIX-compliant shell function for managing multiple node.js versions. In versions 0.31.2 through 0.40.5, `nvm_ls` filters installed versions with a sed program that embeds the requested version pattern in a `\#...#` address, escaping `.` (and, since 0.40.4, `#`) but not backslash. A version string containing `#` (or `\#`) therefore closes the address early, and the rest of it is parsed as sed commands: with GNU sed, the `e` command runs a shell command as the user; with BSD sed, the `w` and `r` commands write and read files. This is reachable whenever an attacker-influenced version string is passed to `nvm use`, `nvm which`, `nvm ls`, `nvm version`, `nvm run`, or `nvm exec`, or to `nvm-exec` via `NODE_VERSION`, and at least one version is installed. nvm's own `.nvmrc` parser strips comments, so a bare `nvm use` is not affected; however, the bash `cdnvm` and zsh `load-nvmrc` auto-switch hooks documented in the README read `.nvmrc` as-is and pass it to `nvm ls` and `nvm version`, so a user with one of those hooks installed runs the attacker's command just by changing into a directory under a malicious `.nvmrc`; scripts that run `nvm use "$(cat .nvmrc)"` are affected the same way. Version 0.40.6 passes any version pattern containing `#` or a newline through the `.nvmrc` content parser first, so no `#` reaches the sed program.
- Published
- Oct 29, 2026
- Updated
- Nov 5, 2026
- EPSS
- 0.1% · 3th percentile
- CWE
- CWE-78
Report tools
Action score
28
Low priority for now.
- CVSS
- 28 / 40 · 7.1 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 0.1%
CISA SSVC decision
- Exploitation
- none
- Automatable
- no
- Technical impact
- total
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- —
- CNA · harborist
- 7.1
- NVD has not scored this yet; the score shown is the CNA’s.
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
Is your version affected? Check itNoroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
—
Versions reported by the vendor
Affected version ranges reported by the assigning authority (harborist). Independent of NVD's CPE analysis and usually ahead of it.
nvm-sh nvm
- 0.31.2 and later · before 0.40.6affected · semver
Same product
nvm-sh: all recordsOther highest-scoring records for the same primary product.
- CVE-2026-121747nvm prints the contents of any readable file through a symlinked .nvmrc26Monitor
- CVE-2026-121746nvm use --save and nvm install --save write through a symlinked .nvmrc, overwriting any file the user can write26Monitor
- CVE-2026-94185nvm alias resolution follows `..` and discloses files outside $NVM_DIR/alias26Monitor
Published before and after this one in the same product
- ← EarlierCVE-2026-1665Jan 29, 2026 · Command Injection in nvm via NVM_AUTH_HEADER in wget code path21Monitor
- ← EarlierCVE-2026-15921Jul 15, 2026 · nvm path traversal via a malicious mirror's LTS codename writes outside the alias directory8Monitor
- Later →CVE-2026-121745Nov 4, 2026 · nvm exposes NVM_AUTH_HEADER to other local users on the curl/wget command line8Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| nvm-sh nvm | 0.40.6 | Vendor (CNA) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
- Published
- Fix recordedsame day
- TodayNov 13, 2026+15 d
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
- vnth4nhntCyStack (https://github.com/vnth4nhnt)finder
- sjh9714 (https://github.com/sjh9714)remediation developer
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
- CVE-2026-1665273 days apartCommand Injection in nvm via NVM_AUTH_HEADER in wget code path21Monitor
Not on record for this CVE: public bounty program.
Technical details
Attack conditions
- Someone with local access to the system can trigger it.
- No account or password is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- Integrity
- Availability
- Attack vector
- Local
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- A
- Scope
- X
Weakness class (CWE)
CWE-78 · Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')CVSS vector
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/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
nvd-secondary
Root cause
User input is inserted as text into a shell command. The shell may interpret special characters in the input as part of the command.
The bug in code
The whole CWE-78 classA representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.
Vulnerable
const host = req.body.host;
exec("ping -c 1 " + host, onResult);Fixed
const host = req.body.host;
if (!/^[a-z0-9.-]{1,253}$/i.test(host)) return res.sendStatus(400);
execFile("ping", ["-c", "1", host], onResult);Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
- Command Line Execution through SQL InjectionCAPEC-108likelihood: Low · Very High
- Command DelimitersCAPEC-15likelihood: High · High
- Exploiting Multiple Input Interpretation LayersCAPEC-43likelihood: Medium · High
- Argument InjectionCAPEC-6likelihood: High · High
- OS Command InjectionCAPEC-88likelihood: High · High
ATT&CK techniques
—
Change log
- SSVC exploitation— → none
- Exploit maturity— → none
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (3 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.