# CVE-2021-41109: LiveQuery publishes user session tokens

> Parse Server leaks user session tokens in LiveQuery payloads, allowing attackers to hijack accounts if users subscribe to the User class.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 30 Sep 2021
- **Updated:** 4 Aug 2024
- **Also known as:** BIT-parse-2021-41109, GHSA-7pr3-p5fm-8r9x

## What is CVE-2021-41109?

CVE-2021-41109 is a high-severity vulnerability in Parseplatform Parse-Server, published on 30 Sep 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Parse Server is an open source backend that can be deployed to any infrastructure that can run Node.js. Prior to version 4.10.4, for regular (non-LiveQuery) queries, the session token is removed from the response, but for LiveQuery payloads it is currently not. If a user has a LiveQuery subscription on the `Parse.User` class, all session tokens created during user sign-ups will be broadcast as part of the LiveQuery payload. A patch in version 4.10.4 removes session tokens from the LiveQuery payload. As a workaround, set `user.acl(new Parse.ACL())` in a beforeSave trigger to make the user private already on sign-up.

Weakness: CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)

## Which versions are affected by CVE-2021-41109?

3 open source packages ship an affected version, including parse-server and parse. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `parse-server` | npm | All versions | 4.10.4 |
| `parse-server` | npm | All versions | 4.10.4 |
| `parse` | Bitnami | All versions | 4.10.4 |

Products: Parseplatform Parse-Server.

## How do I fix CVE-2021-41109?

Upgrade parse-server to 4.10.4 or later.

## Is CVE-2021-41109 being exploited?

There is no known exploitation of CVE-2021-41109 in the wild and no public exploit code.

## Other vulnerabilities in Parseplatform Parse-Server

- [CVE-2026-30966](https://insights.sbomify.com/CVE-2026-30966/): Parse Server role escalation and CLP bypass via direct `_Join` table write (critical 10.0)
- [CVE-2024-27298](https://insights.sbomify.com/CVE-2024-27298/): Parse Server literalizeRegexPart SQL Injection (critical 10.0)
- [CVE-2022-24760](https://insights.sbomify.com/CVE-2022-24760/): Command Injection in Parse server (critical 10.0)
- [CVE-2026-30965](https://insights.sbomify.com/CVE-2026-30965/): Parse Server session token exfiltration via `redirectClassNameForKey` query parameter (critical 9.9)
- [CVE-2023-36475](https://insights.sbomify.com/CVE-2023-36475/): Parse Server vulnerable to remote code execution via MongoDB BSON parser through prototype pollution (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-41109 and fix it if it is affected.

What it is: CVE-2021-41109 is a high-severity vulnerability in Parseplatform Parse-Server, published on 30 Sep 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-41109 in the wild and no public exploit code.

Affected packages and fixed versions:
- parse-server (npm): affected all versions; fixed in 4.10.4
- parse-server (npm): affected all versions; fixed in 4.10.4
- parse (Bitnami): affected all versions; fixed in 4.10.4

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-2021-41109/ (Markdown: https://insights.sbomify.com/CVE-2021-41109/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-41109
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-41109
- OSV: https://osv.dev/vulnerability/CVE-2021-41109

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-41109/
Summaries are generated and may contain mistakes; the official description above is the record.