pnpm: Insertion of Sensitive Information Into Sent Data
CVE-2026-101043 is a high-severity insertion of sensitive information into sent data vulnerability in pnpm, with a CVSS 3.1 base score of 7.4 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. The record lists versions 11.11.0, 10.34.5 as the first without the flaw, so updating pnpm to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.29% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update pnpm to 11.11.0 or 10.34.5, whichever matches your release line, or a later version.
- Read the advisory on github.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
- Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Pnpm | pnpm | 11.0.0 up to, but not including, 11.11.0; 10.7.0 up to, but not including, 10.34.5 | 11.11.0, 10.34.5 |
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- RequiredA user must take an action such as opening a file or link.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- NoneNothing can be modified.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N. Scored by CNA (vulncheck.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 8.3 | High | CNA (vulncheck.com) |
| CVSS 3.1 | 7.4 | High | CNA (vulncheck.com) |
Official description
pnpm versions 11.0.0 before 11.11.0 and 10.7.0 before 10.34.5 expand ${VAR} environment-variable placeholders in the httpProxy, httpsProxy, and noProxy settings read from a project's pnpm-workspace.yaml. Because the manifest is repository-controlled and the proxy keys were omitted from the request-destination key set that otherwise suppresses placeholder expansion for untrusted manifests (as already done for registry, pnprServer, registries and namedRegistries), an attacker who controls a repository's pnpm-workspace.yaml can cause a victim who clones the repository and runs a pnpm command (e.g. pnpm install) to expand environment secrets such as NPM_TOKEN or GITHUB_TOKEN into a proxy hostname or userinfo and route install traffic — and the corresponding DNS lookups — through an attacker-controlled host. The exfiltration occurs during configuration loading, before any lifecycle script executes. Fixed in pnpm 11.11.0 and 10.34.5.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Insertion of Sensitive Information Into Sent Data
The code transmits data to another actor, but a portion of the data includes sensitive information that should not be accessible to that actor.
How developers prevent this class of flaw
- Specify which data in the software should be regarded as sensitive. Consider which types of users should have access to which types of data.
- Ensure that any possibly sensitive data specified in the requirements is verified with designers to ensure that it is either a calculated risk or mitigated elsewhere. Any information that is not necessary to the functionality should be removed in order to lower both the overhead and the possibility of security sensitive data being sent.
- Setup default error messages so that unexpected errors do not disclose sensitive information.
More Insertion of Sensitive Information Into Sent Data vulnerabilities (CWE-201)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Other references
Other vulnerabilities in pnpm
- 7.1 High severity
- 7.5 High severity
- 7.1 High severity
- 7.1 High severity
- 8.2 High severity
- 7.1 High severity
Recent Insertion of Sensitive Information Into Sent Data vulnerabilities
- 7.5 High severity
- 8.2 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
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