# CVE-2026-51876: Missing authorization in n/a

> Unauthenticated attackers can overwrite book metadata and content by reusing exposed book IDs in the confirmation flow.

- **Severity:** Critical 9.1 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 1 Oct 2026
- **Updated:** 5 Oct 2026
- **Also known as:** GHSA-h434-cpxm-mqxr

## What is CVE-2026-51876?

CVE-2026-51876 is a critical missing authorization vulnerability in n/a, published on 1 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

DeepTutor 1.4.0 contains an authorization bypass vulnerability in the book confirmation flow. An unauthenticated or unauthorized caller can reuse a publicly exposed book_id to submit a confirm-proposal request for an existing book, causing unauthorized overwrites of persisted metadata and spine content.

Weakness: CWE-285 (Improper Authorization)

## Which versions are affected by CVE-2026-51876?


## How do I fix CVE-2026-51876?

No fix has been published for CVE-2026-51876 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-51876 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-51876 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-51876 and fix it if it is affected.

What it is: CVE-2026-51876 is a critical missing authorization vulnerability in n/a, published on 1 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-51876 exists.

Affected product: n/a. 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-2026-51876/ (Markdown: https://insights.sbomify.com/CVE-2026-51876/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-51876
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-51876
- OSV: https://osv.dev/vulnerability/CVE-2026-51876

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-51876/
Summaries are generated and may contain mistakes; the official description above is the record.