# CVE-2026-91860: Prototype Pollution in Vaadin Charts and Component Base via Unfiltered Deep Merge > Prototype pollution in Vaadin Charts and Component Base allows attackers to inject properties into Object.prototype, potentially leading to code execution or security bypasses. - **Severity:** Medium 6.3 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N`) - **Exploited in the wild:** Not known - **Login needed:** Not needed - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** No - **Published:** 30 Sep 2026 - **Updated:** 30 Sep 2026 - **Also known as:** GHSA-48v4-h5mw-72ww ## What is CVE-2026-91860? CVE-2026-91860 is a medium-severity vulnerability in @vaadin/charts, published on 30 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim. ### Official description A prototype pollution vulnerability exists in the deep merge helpers of Vaadin Charts and Vaadin Component Base. Merging an object the application does not control into a chart configuration or into a component's i18n property writes onto Object.prototype, making the injected properties visible to every object in the running application. Users of affected versions should apply the following mitigation or upgrade. Releases that have fixed this issue include: Product version Vaadin 23.0.0 - 23.6.13 Vaadin 24.0.0 - 24.9.20 Vaadin 24.10.0 - 24.10.9 Vaadin 25.0.0 - 25.1.11 Vaadin 25.2.0 - 25.2.6 Mitigation Upgrade to 23.6.14 Upgrade to 24.9.21 Upgrade to 24.10.10 Upgrade to 25.1.12 Upgrade to 25.2.7 or newer Please note that Vaadin versions 10-13 and 15-22 are no longer supported and you should update either to the latest 23, 24, 25 version. Artifacts Maven coordinates Vulnerable versions Fixed version com.vaadin:vaadin 23.0.0 - 23.6.13 >=23.6.14 com.vaadin:vaadin 24.0.0 - 24.9.20 >=24.9.21 com.vaadin:vaadin 24.10.0 - 24.10.9 >=24.10.10 com.vaadin:vaadin 25.0.0 - 25.1.11 >=25.1.12 com.vaadin:vaadin 25.2.0 - 25.2.6 >=25.2.7 com.vaadin:vaadin-core 24.7.0 - 24.9.20 >=24.9.21 com.vaadin:vaadin-core 24.10.0 - 24.10.9 >=24.10.10 com.vaadin:vaadin-core 25.0.0 - 25.1.11 >=25.1.12 com.vaadin:vaadin-core 25.2.0 - 25.2.6 >=25.2.7 com.vaadin:vaadin-charts-flow 23.0.0 - 23.6.13 >=23.6.14 com.vaadin:vaadin-charts-flow 24.0.0 - 24.9.20 >=24.9.21 com.vaadin:vaadin-charts-flow 24.10.0 - 24.10.9 >=24.10.10 com.vaadin:vaadin-charts-flow 25.0.0 - 25.1.11 >=25.1.12 com.vaadin:vaadin-charts-flow 25.2.0 - 25.2.6 >=25.2.7 npm packages npm package Vulnerable versions Fixed version @vaadin/charts 23.0.0 - 23.6.4 >=23.6.5 @vaadin/charts 24.0.0 - 24.9.17 >=24.9.18 @vaadin/charts 24.10.0 - 24.10.4 >=24.10.5 @vaadin/charts 25.0.0 - 25.1.11 >=25.1.12 @vaadin/charts 25.2.0 - 25.2.8 >=25.2.9 @vaadin/component-base 24.7.0 - 24.9.17 >=24.9.18 @vaadin/component-base 24.10.0 - 24.10.4 >=24.10.5 @vaadin/component-base 25.0.0 - 25.1.11 >=25.1.12 @vaadin/component-base 25.2.0 - 25.2.8 >=25.2.9 Weakness: CWE-1321 (Improperly Controlled Modification of Object Prototype Attributes) ## Which versions are affected by CVE-2026-91860? ## How do I fix CVE-2026-91860? No fix has been published for CVE-2026-91860 yet. Limit exposure of the affected software until one is available. ## Is CVE-2026-91860 being exploited? There is no known exploitation of CVE-2026-91860 in the wild and no public exploit code. ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-91860 and fix it if it is affected. What it is: CVE-2026-91860 is a medium-severity vulnerability in @vaadin/charts, published on 30 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim. Exploitation: There is no known exploitation of CVE-2026-91860 in the wild and no public exploit code. Affected product: @vaadin/charts. No package-level version data is available, so check the vendor advisory linked from the reference page. Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2026-91860/ (Markdown: https://insights.sbomify.com/CVE-2026-91860/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-91860 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-91860 - OSV: https://osv.dev/vulnerability/CVE-2026-91860 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-91860/ Summaries are generated and may contain mistakes; the official description above is the record.