CVE-2026-35205
Helm 4.0.0 – 4.1.4
Raw vector
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XSummary
CVE-2026-35205 is a high-severity Failing Open (CWE-636) vulnerability in Helm Helm. Its CVSS base score is 8.4 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Supply Chain Compromise (T1195); ranked at the 13th 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 CP-12 (Safe Mode) and SC-13 (Cryptographic Protection) — 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-2026-35205 affects Helm, a package manager for Kubernetes Charts, in versions 4.0.0 through 4.1.3. The vulnerability allows Helm to install plugins that lack a provenance file (.prov file) even when signature verification is explicitly required. This flaw, classified under CWE-636 (Not Failing Securely), enables the bypass of integrity checks intended to ensure plugin authenticity and trustworthiness. The issue carries a CVSS v3.1 base score of 7.8 (AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H) and was published on April 9, 2026.
An attacker with local access to the victim's system can exploit this vulnerability by providing a malicious plugin archive missing the required .prov file. No special privileges are needed (PR:N), but exploitation requires low complexity and user interaction, such as a user running the `helm plugin install` command on the attacker's crafted plugin while signature verification is enabled. Successful exploitation grants high impacts on confidentiality, integrity, and availability, potentially allowing arbitrary code execution, data theft, or system compromise within the context of the Helm process.
Helm advisories and release notes recommend upgrading to version 4.1.4, which addresses the issue via a specific commit enforcing provenance file presence during signed plugin installations. The official security advisory (GHSA-q5jf-9vfq-h4h7) and release page detail the fix, while Helm documentation on provenance files explains the .prov file's role in verifying plugin signatures and origins. Practitioners should verify plugin sources and enable strict verification policies until patching.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-20901
Vulnerability Data
Helm is a package manager for Charts for Kubernetes. From 4.0.0 to 4.1.3, Helm will install plugins missing provenance (.prov file) when signature verification is required. This vulnerability is fixed in 4.1.4.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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- 14 hardening rules · 5 OS baselines
V3.2.1V7.4.1V8.3.3V10.3.4
Mitigating Controls (NIST 800-53 r5) AI
SC-24 directly requires the system to fail to a known state that preserves security properties, structurally stopping fallback to a less-secure mode.
SI-17 mandates explicit fail-safe procedures that activate on indicated failures, preventing the insecure fallback behavior.
CP-12 forces entry into a safe mode on detected conditions, limiting exposure but not covering every failure path.
Requiring cryptographic protection mechanisms forces correct signature verification to be implemented for data protection.
Mandating integrity verification tools directly requires proper cryptographic signature checking to detect unauthorized changes.
SA-8 requires application of engineering principles that include fail-secure design, reducing the likelihood the weakness is introduced.
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.
Digital signatures are explicitly cited to protect integrity of data-at-rest, so proper verification directly mitigates the weakness.
Digital signatures are explicitly cited to protect integrity of data-in-transit, so proper verification directly mitigates the weakness.
Secure-development practices explicitly include designing error and failure handling to remain in a secure state.
Requires assessing authenticity and integrity of acquired assets, which commonly relies on signature verification but is limited to pre-acquisition.
Least-privilege policy and enforcement directly counters the permissive-access fallback example in the CWE.
Hardened baselines and configuration management reduce the chance that error paths default to insecure settings.
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.
Establishing approved cryptographic solutions and usage practices lowers the probability that signature-verification steps will be omitted or incorrectly implemented.
The control forces an explicit evaluation step before any response, reducing the chance that a failure condition will default to an unsafe open state.
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 (2 rules)
- V-248574 YUM must be configured to prevent the installation of patches, service packs, device drivers, or OL 8 system components that have not been digitally signed using a certificate that is recognized and approved by the organization. prevents CWE-347
- 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-347
Oracle Linux 9 (2 rules)
- V-271525 OL 9 must have GPG signature verification enabled for all software repositories. prevents CWE-347
- V-271523 OL 9 must check the GPG signature of locally installed software packages before installation. prevents CWE-347
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-347
- 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-347
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-347
RHEL 9 (1 rule)
- V-257822 RHEL 9 must have GPG signature verification enabled for all software repositories. prevents CWE-347