# CVE-2019-1000021: slixmpp Incorrect Access Control

> An incorrect access control in slixmpp allows contacts to view private data if the user publishes to a PEP node without explicit privacy configuration.

- **Severity:** High 7.5 (`CVSS:3.0/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:** 4 Feb 2019
- **Updated:** 5 Aug 2024
- **Also known as:** DEBIAN-CVE-2019-1000021, GHSA-4g62-mfwx-4q48, PYSEC-2019-121, UBUNTU-CVE-2019-1000021, openSUSE-SU-2019:0163-1, openSUSE-SU-2019:0169-1

## What is CVE-2019-1000021?

CVE-2019-1000021 is a high-severity missing authorization vulnerability in n/a, published on 4 Feb 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

slixmpp version before commit 7cd73b594e8122dddf847953fcfc85ab4d316416 contains an incorrect Access Control vulnerability in XEP-0223 plugin (Persistent Storage of Private Data via PubSub) options profile, used for the configuration of default access model that can result in all of the contacts of the victim can see private data having been published to a PEP node. This attack appears to be exploitable if the user of this library publishes any private data on PEP, the node isn't configured to be private. This vulnerability appears to have been fixed in commit 7cd73b594e8122dddf847953fcfc85ab4d316416 which is included in slixmpp 1.4.2.

## Which versions are affected by CVE-2019-1000021?

3 open source packages ship an affected version, including slixmpp. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `slixmpp` | PyPI | All versions | 1.4.2 |
| `slixmpp` | PyPI | All versions | 1.4.2 |
| `slixmpp` | PyPI | All versions | 1.4.2 |
| `python-slixmpp` | SUSE:Package Hub 15 | All versions | 1.3.0-bp150.3.3.1 |

Products: Slixmpp Project Slixmpp.

## How do I fix CVE-2019-1000021?

Upgrade slixmpp to 1.4.2 or later.

## Is CVE-2019-1000021 being exploited?

There is no known exploitation of CVE-2019-1000021 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2022-45197](https://insights.sbomify.com/CVE-2022-45197/): Slixmpp lacks SSL Certificate hostname validation in XMLStream (high 7.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-1000021 and fix it if it is affected.

What it is: CVE-2019-1000021 is a high-severity missing authorization vulnerability in n/a, published on 4 Feb 2019. 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-2019-1000021 in the wild and no public exploit code.

Affected packages and fixed versions:
- slixmpp (PyPI): affected all versions; fixed in 1.4.2
- slixmpp (PyPI): affected all versions; fixed in 1.4.2
- slixmpp (PyPI): affected all versions; fixed in 1.4.2

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-2019-1000021/ (Markdown: https://insights.sbomify.com/CVE-2019-1000021/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-1000021
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-1000021
- OSV: https://osv.dev/vulnerability/CVE-2019-1000021

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-1000021/
Summaries are generated and may contain mistakes; the official description above is the record.