How severe is CVE-2026-55849?

No CVSS score has been assigned to CVE-2026-55849 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-55849?

CVE-2026-55849 affects the following packages: @cyclonedx/cyclonedx-npm (npm). Ecosystems affected: npm.

How do I fix CVE-2026-55849?

Update @cyclonedx/cyclonedx-npm to 5.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-55849 is resolved across your whole dependency graph.

How do I detect CVE-2026-55849 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @cyclonedx/cyclonedx-npm, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-55849 if there is no patch (or I can't update yet)?

Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does.

Is CVE-2026-55849 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-55849 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-55849?

CVE-2026-55849 has an EPSS (Exploit Prediction Scoring System) score of 0.2%, placing it in the 13th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-55849?

CVE-2026-55849 is classified as OS Command Injection (CWE-78). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2026-55849 published, and has it been updated?

CVE-2026-55849 was published on July 8, 2026 and was last updated on August 12, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦 npm

Not in CISA KEV

CVE-2026-55849 — @cyclonedx/cyclonedx-npm

Fix: CycloneDX/cyclonedx-node-npm@9f64625

CVE-2026-55849 is a OS Command Injection vulnerability in @cyclonedx/cyclonedx-npm. A fix is available for @cyclonedx/cyclonedx-npm — see the affected versions and patch details below.

@cyclonedx/cyclonedx-npm: Shell Injection via Unsanitized `--workspace` Argument

Also known asGHSA-v75r-vx73-82pj

Published

Jul 8, 2026

Updated

Aug 12, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Oct 5, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

A successful exploit gives an attacker total control of the affected component, not partial access.
CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-55849.

EPSS Exploitation Probability

via FIRST.org ↗

0.2%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs13th percentile — riskier than 13% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

1 pkg affected

How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.

5other npm packages depend on this — each one inherits the vulnerability until it's patched upstream

@cyclonedx/cyclonedx-npmnpm

616Kdownloads / week

Description

Summary

A command injection vulnerability exists in @cyclonedx/cyclonedx-npm when the CLI is invoked with the --workspace <value> option while the environment variable npm_execpath is unset or empty.
User‑supplied --workspace values are passed to a subshell without proper sanitization, enabling attackers to inject arbitrary OS commands.
This issue corresponds to CWE‑78: Improper Neutralization of Special Elements used in an OS Command.

The vulnerability was fixed in version 5.0.0.

Vulnerability Details

When cyclonedx-npm is executed with the --workspace option, the provided argument is incorporated into an internal shell command.
If the environment variable npm_execpath is set, the tool uses the npm executable directly and no injection occurs.
However, when npm_execpath is unset or empty, the tool falls back to spawning a subshell and interpolating the --workspace value directly into the command string without proper escaping or neutralization.

As a result, specially crafted workspace names can break out of the intended command context and execute arbitrary commands with the privileges of the invoking user.

Impact

An attacker who can influence the value passed to --workspace can execute arbitrary OS commands.
This may lead to:

Arbitrary command execution
Data exfiltration
Local privilege escalation (depending on how the tool is used)
Modification or destruction of files accessible to the user running the CLI

The vulnerability affects only scenarios where:

The user invokes cyclonedx-npm with --workspace <value>, and
The environment variable npm_execpath is unset or empty

Exploitation Conditions (High‑Level)

Exploitation requires the attacker to supply or influence the --workspace value passed to the CLI.
If the tool falls back to its subshell execution path, specially crafted workspace identifiers can cause unintended command execution.
No exploit code is included here to avoid providing weaponizable examples.

Root Cause

The CLI constructs a shell command using untrusted input from the --workspace option.
Because the fallback code path does not sanitize or escape the workspace value, special shell metacharacters (e.g., ;, &&, |) are interpreted by the shell, enabling command injection.

This behavior matches CWE‑78.

Fix

The vulnerability was resolved in PR #1476, which ensures that workspace values are handled safely and are no longer passed to a subshell in an unsafe manner.

The fix is included in @cyclonedx/cyclonedx-npm version 5.0.0.

Remediation

Upgrade to version 5.0.0 or later, which contains the complete fix.
As a temporary mitigation for older versions, ensure that the environment variable npm_execpath is set before invoking the tool.
Avoid passing untrusted or user‑controlled values to the --workspace option.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`@cyclonedx/cyclonedx-npm`	≥ 2.1.0&&< 5.0.0	5.0.0`npm install @cyclonedx/cyclonedx-npm@5.0.0`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for @cyclonedx/cyclonedx-npm, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update @cyclonedx/cyclonedx-npm to 5.0.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-55849 is resolved across your whole dependency graph.
Workarounds
Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does.

Frequently Asked Questions

## Summary A command injection vulnerability exists in `@cyclonedx/cyclonedx-npm` when the CLI is invoked with the `--workspace <value>` option while the environment variable `npm_execpath` is unset or empty. User‑supplied `--workspace` values are passed to a subshell without proper sanitization, enabling attackers to inject arbitrary OS commands. This issue corresponds to **CWE‑78**: Improper Neutralization of Special Elements used in an OS Command. The vulnerability was fixed in version [5.0.0][v5.0.0]. ## Vulnerability Details When `cyclonedx-npm` is executed with the `--workspace` o

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