dbcve.org
ArboristApplication · Npmjs

CVE-2021-39134

HIGH · 7.8 CVSS v3.1 Published 2021-08-31
Fix available
A fix is available. Upgrade to 1.0.1.1 / 2.8.2 or later.
See remediation →
81/100
Remediation priority · High
No privileges Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
`@npmcli/arborist`, the library that calculates dependency trees and manages the `node_modules` folder hierarchy for the npm command line interface, aims to guarantee that package dependency contracts will be met, and the extraction of package contents will always be performed into the expected folder. This is, in part, accomplished by resolving dependency specifiers defined in `package.json` manifests for dependencies with a specific name, and nesting folders to resolve conflicting dependencies. When multiple dependencies differ only in the case of their name, Arborist's internal data structure saw them as separate items that could coexist within the same level in the `node_modules` hierarchy. However, on case-insensitive file systems (such as macOS and Windows), this is not the case. Combined with a symlink dependency such as `file:/some/path`, this allowed an attacker to create a situation in which arbitrary contents could be written to any location on the filesystem. For example, a package `pwn-a` could define a dependency in their `package.json` file such as `"foo": "file:/some/path"`. Another package, `pwn-b` could define a dependency such as `FOO: "file:foo.tgz"`. On case-insensitive file systems, if `pwn-a` was installed, and then `pwn-b` was installed afterwards, the contents of `foo.tgz` would be written to `/some/path`, and any existing contents of `/some/path` would be removed. Anyone using npm v7.20.6 or earlier on a case-insensitive filesystem is potentially affected. This is patched in @npmcli/arborist 2.8.2 which is included in npm v7.20.7 and above.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis

A detailed technical summary for this CVE is being prepared.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
ArboristApplication
Affected:< 2.8.2
GraalvmApplication
Affected:= 20.3.3= 21.2.0
Sinec Infrastructure Network ServicesApplication
Affected:< 1.0.1.1

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 1.0.1.1 / 2.8.2 or later
Fixed in 1.0.1.12.8.2
Vendor patch cert-portal.siemens.com →
Recommended fix High confidence

@npmcli/arborist >= 2.8.2, or npm >= 7.20.7, or Graalvm >= patched version per Oracle advisory, or Sinec Infrastructure Network Services >= 1.0.1.1

  1. Upgrade @npmcli/arborist to version 2.8.2 or later. If using npm, upgrade npm to version 7.20.7 or later which includes the fixed arborist version.
  2. For Graalvm users: Note that Graalvm versions 20.3.3 and 21.2.0 are listed as affected. Check Oracle's official security advisories for Graalvm-specific patches or consider upgrading to a newer Graalvm version that includes the fixed npm/arborist.
  3. For Sinec Infrastructure Network Services users: Upgrade to version 1.0.1.1 or later as specified in the Siemens security advisory (see SSA-389290).
Caveat Upgrading npm or arborist is low risk; however, test in a staging environment first as with any dependency update. Graalvm and Sinec users should review their respective vendor documentation for any compatibility notes.

Generated from the published advisory — verify against the referenced sources before acting.

We can perform the upgrade in your staging environment and verify nothing breaks — typical engagement from $1,950. Get the upgrade done

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-39134 in production — separate from our analysis above.

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