CVE-2016-3956
mediumpriority · track · 32EPSS 0.055 · 93 %ileEUUSEPSS · scored 2026-10-27
The CLI in npm before 2.15.1 and 3.x before 3.8.3, as used in Node.js 0.10 before 0.10.44, 0.12 before 0.12.13, 4 before 4.4.2, and 5 before 5.10.0, includes bearer tokens with arbitrary requests, which allows remote HTTP servers to obtain sensitive information by reading Authorization headers.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (92)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- GHSA-m5h6-hr3q-22h5npm Token Leak in npm2018-07-31ghsa · osvUS
Affected versions of the `npm` package include the bearer token of the logged in user in every request made by the CLI, even if the request is not directed towards the user's active registry. An attacker could create an HTTP server to collect tokens, and by various means including but not limited to install scripts, cause the npm CLI to make a request to that server, which would compromise the user's token. This compromised token could be used to do anything that the user could do, including publishing new packages. ## Recommendation 1. Update npm with `npm install npm@latest -g` 2. [Revoke your Tokens](https://www.npmjs.com/settings/tokens) 3. Enable [Two-Factor Authentication](https://docs.npmjs.com/getting-started/using-two-factor-authentication)
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (19)
External citations — patches, advisories, analysis.
- http://blog.npmjs.org/post/142036323955/fixing-a-bearer-token-vulnerabilitycnnvd
- http://www-01.ibm.com/support/docview.wss?uid=swg21980827cnnvd
- https://github.com/npm/npm/commit/f67ecad59e99a03e5aad8e93cd1a086ae087cb29cnnvd
- https://github.com/npm/npm/commit/fea8cc92cee02c720b58f95f14d315507ccad401cnnvd
- https://github.com/npm/npm/issues/8380cnnvd
- https://nodejs.org/en/blog/vulnerability/npm-tokens-leak-march-2016/cnnvd
- https://www.auscert.org.au/bulletins/ESB-2020.4254/cnnvd
- http://blog.npmjs.org/post/142036323955/fixing-a-bearer-token-vulnerabilityenisa_euvd
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