# CVE-2021-25964: Stored Cross-Site Scripting (XSS) in Calibre-web via Description Field in Metadata

> An attacker with metadata edit access can inject JavaScript into the description field, leading to stored XSS when victims view the file.

- **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:** No
- **Published:** 4 Oct 2021
- **Updated:** 30 Apr 2025
- **Also known as:** GHSA-8gr4-jgmh-5g8w

## What is CVE-2021-25964?

CVE-2021-25964 is a medium-severity cross-site scripting vulnerability in OzzieIsaacs calibreweb, published on 4 Oct 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

In “Calibre-web” application, v0.6.0 to v0.6.12, are vulnerable to Stored XSS in “Metadata”. An attacker that has access to edit the metadata information, can inject JavaScript payload in the description field. When a victim tries to open the file, XSS will be triggered.

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

## Which versions are affected by CVE-2021-25964?

It affects 1 product.


Products: Janeczku Calibre-Web.

## How do I fix CVE-2021-25964?

No fix has been published for CVE-2021-25964 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-25964 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-25964 exists.

## Other vulnerabilities in OzzieIsaacs calibreweb

- [CVE-2022-30765](https://insights.sbomify.com/CVE-2022-30765/): SQL injection in calibreweb (critical 9.8)
- [CVE-2020-12627](https://insights.sbomify.com/CVE-2020-12627/): Hardcoded credentials in n/a (critical 9.8)
- [CVE-2022-0990](https://insights.sbomify.com/CVE-2022-0990/): Server-Side Request Forgery (SSRF) in janeczku/calibre-web (critical 9.3)
- [CVE-2022-0767](https://insights.sbomify.com/CVE-2022-0767/): Server-Side Request Forgery (SSRF) in janeczku/calibre-web (critical 9.1)
- [CVE-2022-0939](https://insights.sbomify.com/CVE-2022-0939/): Server-Side Request Forgery (SSRF) in janeczku/calibre-web (critical 9.0)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-25964 and fix it if it is affected.

What it is: CVE-2021-25964 is a medium-severity cross-site scripting vulnerability in OzzieIsaacs calibreweb, published on 4 Oct 2021. Any signed-in user can exploit it over the 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-2021-25964 exists.

Affected product: OzzieIsaacs calibreweb. 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-2021-25964/ (Markdown: https://insights.sbomify.com/CVE-2021-25964/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-25964
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-25964
- OSV: https://osv.dev/vulnerability/CVE-2021-25964

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-25964/
Summaries are generated and may contain mistakes; the official description above is the record.