Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HSummary
CVE-2026-34841 is a critical-severity Download of Code Without Integrity Check (CWE-494) vulnerability in Usebruno Bruno. Its CVSS base score is 9.8 (Critical).
Operationally, exploitation aligns with the MITRE ATT&CK technique Supply Chain Compromise (T1195); ranked at the 14th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified map to CM-14 (Signed Components) and SA-11 (Developer Testing and Evaluation) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2026-34841 is a supply chain vulnerability affecting Bruno, an open source IDE for exploring and testing APIs, in versions prior to 3.2.1. The issue arises from compromised versions of the axios npm package, which introduced a hidden dependency that deploys a cross-platform Remote Access Trojan (RAT). It specifically impacts users of the @usebruno/cli package who ran npm install between 00:21 UTC and approximately 03:30 UTC on March 31, 2026. The vulnerability is rated critical with a CVSS v3.1 score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H) and is associated with CWE-494 and CWE-506.
Any user executing the affected npm install command during the specified time window on March 31, 2026, could unwittingly deploy the RAT, with no privileges, authentication, or additional user interaction required. Attackers leveraging this supply chain compromise achieve high-impact remote access, enabling full compromise of confidentiality, integrity, and availability on the victim's system across platforms.
Advisories and patches, detailed in GitHub issues such as axios#10604 and Bruno pull request #7632, along with Bruno's security advisory GHSA-658g-p7jg-wx5g, recommend immediate upgrade to Bruno version 3.2.1 to remove the compromised dependency and prevent RAT deployment. Additional analysis is available from Aikido.dev.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-19354
Vulnerability Data
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…
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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
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 12 hardening rules · 5 OS baselines
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Mitigating Controls (NIST 800-53 r5) AI
Requires digital signature verification before component installation, directly stopping execution of code downloaded without integrity checks.
Developer testing and evaluation can discover embedded malicious code before release.
Detonation chambers can reveal embedded malicious code through controlled execution analysis.
Employs integrity verification tools that can identify missing or failed checks on downloaded software after the fact.
Tamper-resistance and detection mechanisms identify malicious code introduced via the supply chain.
Component authenticity requirements reduce the chance malicious code is embedded by developers or suppliers.
Mitigating Controls (NIST CSF 2.0) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.
Directly requires assessing authenticity/integrity of software before acquisition and use, preventing unverified downloads.
Requires cryptographic integrity protections (signatures/hashes) for data-in-transit, covering downloaded code.
Prevents execution of unauthorized software, blocking the outcome of an unchecked download.
Secure SDLC practices directly prevent introduction of malicious code during development.
Due diligence prior to supplier relationships helps avoid sources of embedded malicious code.
Supplier risk assessment reduces likelihood of receiving products containing malicious code.
Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI
Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.
Mandating integrity checks, digital signatures, and origin tracing for ICT components directly reduces the chance that code or firmware lacking an integrity check will be accepted into the organisation’s environment.
Checks that executed code has not been tampered with and monitoring for malware-associated activity reduce the likelihood that hidden malicious code remains active.
Banning unapproved or unknown software and requiring testing plus authorization reduces the chance that hidden malicious code will be introduced into production environments.
Requiring suppliers to disclose vulnerabilities and mandating verified updates lowers the chance that code lacking integrity checks will be deployed.
Hardening callouts derived
Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (authoritative rows only; rows rated `none` are excluded).
Oracle Linux 8 (1 rule)
- V-248575 OL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. prevents CWE-494
Oracle Linux 9 (2 rules)
- V-271524 OL 9 must check the GPG signature of software packages originating from external software repositories before installation. prevents CWE-494
- V-271452 OL 9 must use a Linux Security Module configured to enforce limits on system services. prevents CWE-506
RHEL 7 (2 rules)
- V-204447 The Red Hat Enterprise Linux operating system must prevent the installation of software, patches, service packs, device drivers, or operating system components from a repository without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. prevents CWE-494
- V-204448 The Red Hat Enterprise Linux operating system must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. prevents CWE-494
RHEL 8 (1 rule)
- V-230264 RHEL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components from a repository without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. prevents CWE-494
RHEL 9 (2 rules)
- V-257820 RHEL 9 must check the GPG signature of software packages originating from external software repositories before installation. prevents CWE-494
- V-258078 RHEL 9 must use a Linux Security Module configured to enforce limits on system services. prevents CWE-506