# CVE-2026-23887: Group-Office has stored XSS vulnerability via unsanitized filenames

> Attackers can inject malicious scripts via unsanitized filenames, potentially hijacking user sessions or executing actions in the browser.

- **Severity:** Medium 5.1 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 21 Jan 2026
- **Updated:** 22 Jan 2026
- **Also known as:** GHSA-3gj5-gvvr-g6hp

## What is CVE-2026-23887?

CVE-2026-23887 is a medium-severity cross-site scripting vulnerability in Intermesh groupoffice, published on 21 Jan 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

Group-Office is an enterprise customer relationship management and groupware tool. In versions 6.8.148 and below, and 25.0.1 through 25.0.79, the application stores unsanitized filenames in the database, which can lead to Stored Cross-Site Scripting (XSS). Users who interact with these specially crafted file names within the Group-Office application are affected. While the scope is limited to the file-viewing context, it could still be used to interfere with user sessions or perform unintended actions in the browser. This issue is fixed in versions 6.8.149 and 25.0.80.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation), CWE-20 (Improper Input Validation)

## Which versions are affected by CVE-2026-23887?

It affects 1 product.


Products: Group-Office Group Office.

## How do I fix CVE-2026-23887?

No fix has been published for CVE-2026-23887 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-23887 being exploited?

There is no known exploitation of CVE-2026-23887 in the wild and no public exploit code.

## Other vulnerabilities in Intermesh groupoffice

- [CVE-2026-25512](https://insights.sbomify.com/CVE-2026-25512/): Group-Office is vulnerable to RCE due to Command Injection via TNEF Attachment Handler (critical 9.4)
- [CVE-2026-25134](https://insights.sbomify.com/CVE-2026-25134/): Group-Office Argument Injection in MaintenanceController::actionZipLanguage (critical 9.4)
- [CVE-2025-63406](https://insights.sbomify.com/CVE-2025-63406/): Code injection in n/a (high 8.8)
- [CVE-2026-25511](https://insights.sbomify.com/CVE-2026-25511/): Group-Office is vulnerable to SSRF and File Read in WOPI service discovery (high 8.2)
- [CVE-2023-46730](https://insights.sbomify.com/CVE-2023-46730/): Server-Side Request Forgery in groupoffice (high 7.4)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-23887 and fix it if it is affected.

What it is: CVE-2026-23887 is a medium-severity cross-site scripting vulnerability in Intermesh groupoffice, published on 21 Jan 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-23887 in the wild and no public exploit code.

Affected product: Intermesh groupoffice. 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-2026-23887/ (Markdown: https://insights.sbomify.com/CVE-2026-23887/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-23887
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-23887
- OSV: https://osv.dev/vulnerability/CVE-2026-23887

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-23887/
Summaries are generated and may contain mistakes; the official description above is the record.