dbcve.org
BrunoApplication · Usebruno

CVE-2026-34841

CRITICAL · 9.8 CVSS v3.1 Published 2026-04-06
Fix available
A fix is available. Upgrade to 3.2.1 or later.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click 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
Bruno is an open source IDE for exploring and testing APIs. Prior to 3.2.1, Bruno was affected by a supply chain attack involving compromised versions of the axios npm package, which introduced a hidden dependency deploying a cross-platform Remote Access Trojan (RAT). Users of @usebruno/cli who ran npm install between 00:21 UTC and ~03:30 UTC on March 31, 2026 may have been impacted. Upgrade to 3.2.1

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 · high confidence

This is a supply chain attack where compromised versions of the axios npm package were inadvertently pulled during a narrow time window (00:21 UTC to ~03:30 UTC on March 31, 2026), introducing a hidden dependency that deployed a cross-platform Remote Access Trojan (RAT). Users of @usebruno/cli who ran npm install during this window are affected.

MitigationImmediately upgrade @usebruno/cli to version 3.2.1 or later. Investigate systems that ran npm install during the affected window for indicators of compromise, as the RAT may have provided remote access to threat actors.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

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
BrunoApplication
Affected:< 3.2.1

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
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check @usebruno/cli installed version
    Run 'npm list @usebruno/cli' in your project directory to see the installed version of the CLI package
    Affected if Version is lower than 3.2.1
  2. Check if npm install ran during the attack window
    Review npm install logs, CI/CD pipeline logs, or container build timestamps for installations between 00:21 UTC and 03:30 UTC on March 31, 2026
    Affected if npm install, npm ci, or package installation commands executed during the affected time window
  3. Inspect axios dependency version
    Run 'npm list axios' to list the axios version installed as a transitive dependency and compare against known-good versions prior to the attack window
    Affected if axios version shows as a recently-fetched version from the compromised window (around March 31, 2026)
  4. Check for suspicious hidden dependencies
    Run 'npm ls --all' to view full dependency tree and look for unexpected or unusual packages that are not direct dependencies of your project
    Affected if Unexpected packages appear in the dependency tree that were not intentionally installed

You are likely affected if @usebruno/cli version is below 3.2.1 AND npm install was executed during the March 31, 2026 00:21-03:30 UTC window, or if unexpected packages appear in your dependency tree.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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 3.2.1 or later
Fixed in 3.2.1
Vendor patch github.com →
Interim mitigation

Immediately upgrade @usebruno/cli to version 3.2.1 or later. Investigate systems that ran npm install during the affected window for indicators of compromise, as the RAT may have provided remote access to threat actors.

Recommended fix High confidence

3.2.1

  1. Check current Bruno CLI version by running: npm list @usebruno/cli
  2. Clear npm cache to remove any potentially compromised packages: npm cache clean --force
  3. Upgrade to version 3.2.1 or later: npm install @usebruno/[email protected]
  4. Verify the installed version: npm list @usebruno/cli
  5. For additional safety, delete node_modules and package-lock.json, then reinstall: rm -rf node_modules package-lock.json && npm install

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

Fix this in Bruno Scoped from the published advisory
  • Consultation2.0 h
  • Implementation1.0 h
  • Testing2.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,060
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,696.

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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-2026-34841 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data