# CVE-2021-26925: Cross-site scripting in n/a

> Attackers can execute arbitrary scripts in victim browsers via crafted CSS in HTML emails, potentially leading to session hijacking or data theft.

- **Severity:** Medium 5.4 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A: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:** Yes
- **Published:** 9 Feb 2021
- **Updated:** 3 Aug 2024
- **Also known as:** BIT-roundcube-2021-26925, DEBIAN-CVE-2021-26925, GHSA-xw9h-8vfr-ppf5, MGASA-2021-0130, UBUNTU-CVE-2021-26925

## What is CVE-2021-26925?

CVE-2021-26925 is a medium-severity cross-site scripting vulnerability in Fedoraproject Fedora, published on 9 Feb 2021. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

Roundcube before 1.4.11 allows XSS via crafted Cascading Style Sheets (CSS) token sequences during HTML email rendering.

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

## Which versions are affected by CVE-2021-26925?

1 open source package ship an affected version, including roundcube. It affects 2 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `roundcube` | Bitnami | All versions | 1.4.11 |

Products: Fedoraproject Fedora, Roundcube Webmail.

## How do I fix CVE-2021-26925?

Upgrade roundcube to 1.4.11 or later.

## Is CVE-2021-26925 being exploited?

There is no known exploitation of CVE-2021-26925 in the wild and no public exploit code.

## Other vulnerabilities in Fedoraproject Fedora

- [CVE-2024-4577](https://insights.sbomify.com/CVE-2024-4577/): PHP-CGI OS Command Injection (critical 9.8, exploited in the wild)
- [CVE-2021-39226](https://insights.sbomify.com/CVE-2021-39226/): Grafana Authentication Bypass (critical 9.8, exploited in the wild)
- [CVE-2019-5544](https://insights.sbomify.com/CVE-2019-5544/): VMware ESXi and Horizon DaaS OpenSLP Heap-Based Buffer Overflow (critical 9.8, exploited in the wild)
- [CVE-2024-4947](https://insights.sbomify.com/CVE-2024-4947/): Google Chromium V8 Type Confusion (critical 9.6, exploited in the wild)
- [CVE-2024-4671](https://insights.sbomify.com/CVE-2024-4671/): Google Chromium Visuals Use-After-Free (critical 9.6, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-26925 and fix it if it is affected.

What it is: CVE-2021-26925 is a medium-severity cross-site scripting vulnerability in Fedoraproject Fedora, published on 9 Feb 2021. 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-2021-26925 in the wild and no public exploit code.

Affected packages and fixed versions:
- roundcube (Bitnami): affected all versions; fixed in 1.4.11

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-2021-26925/ (Markdown: https://insights.sbomify.com/CVE-2021-26925/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-26925
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-26925
- OSV: https://osv.dev/vulnerability/CVE-2021-26925

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-26925/
Summaries are generated and may contain mistakes; the official description above is the record.