# CVE-2026-27964: FacturaScripts: Reflected Cross-Site Scripting (XSS) via Cookie Manipulation > Attackers can execute arbitrary scripts in victim browsers by manipulating the fsNick cookie, bypassing logout redirects. - **Severity:** Low 3.9 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N`) - **Exploited in the wild:** Not known - **Login needed:** Any signed-in user - **Attackable:** Local or same network only - **Victim action needed:** A user has to click or open something - **Fix available:** No - **Published:** 18 May 2026 - **Updated:** 19 May 2026 - **Also known as:** GHSA-gq5c-rw37-g46c ## What is CVE-2026-27964? CVE-2026-27964 is a low-severity cross-site scripting vulnerability in NeoRazorX facturascripts, published on 18 May 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link. ### Official description FacturaScripts is an open source accounting and invoicing software. Versions 2025.7 and prior contain a Reflected Cross-Site Scripting (XSS) vulnerability through the fsNick cookie parameter. The application reflects the cookie's value directly into the HTML without sanitization. The fsNick cookie is rendered into the DOM without encoding. While the server does reject the modified session and forces a logout, the HTML containing the payload reaches the browser first. This lets the script execute immediately upon load, effectively beating the redirect. This issue has been fixed in version 2025.8. Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation) ## Which versions are affected by CVE-2026-27964? 2 open source packages ship an affected version, including facturascripts/facturascripts. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `facturascripts/facturascripts` | Packagist | All versions to 2025.71 | None | | `facturascripts/facturascripts` | Packagist | All versions to 2025.71 | None | ## How do I fix CVE-2026-27964? No fix has been published for CVE-2026-27964 yet. Limit exposure of the affected software until one is available. ## Is CVE-2026-27964 being exploited? It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-27964 exists. ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-27964 and fix it if it is affected. What it is: CVE-2026-27964 is a low-severity cross-site scripting vulnerability in NeoRazorX facturascripts, published on 18 May 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link. Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-27964 exists. Affected packages and fixed versions: - facturascripts/facturascripts (Packagist): affected all versions up to 2025.71; no fix listed - facturascripts/facturascripts (Packagist): affected all versions up to 2025.71; no fix listed 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-2026-27964/ (Markdown: https://insights.sbomify.com/CVE-2026-27964/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-27964 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-27964 - OSV: https://osv.dev/vulnerability/CVE-2026-27964 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-27964/ Summaries are generated and may contain mistakes; the official description above is the record.