# CVE-2023-27891: Insufficient Session Expiration in pretix

> Attackers can authorize OAuth applications from logged-out sessions, potentially leading to account takeover in pretix.

- **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:** 6 Mar 2023
- **Updated:** 6 Mar 2025
- **Also known as:** GHSA-r76w-3wwq-jv6v, PYSEC-2023-42

## What is CVE-2023-27891?

CVE-2023-27891 is a high-severity authentication bypass vulnerability in n/a, published on 6 Mar 2023. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

rami.io pretix before 4.17.1 allows OAuth application authorization from a logged-out session. The fixed versions are 4.15.1, 4.16.1, and 4.17.1.

Weakness: CWE-613 (DEPRECATED: Insufficient Session Expiration)

## Which versions are affected by CVE-2023-27891?

7 open source packages ship an affected version, including pretix. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `pretix` | PyPI | All versions | 4.15.1 |
| `pretix` | PyPI | All versions | 4.15.1 |
| `pretix` | PyPI | All versions | 4.17.1 |
| `pretix` | PyPI | From 4.16.0 | 4.16.1 |
| `pretix` | PyPI | From 4.16.0 | 4.16.1 |
| `pretix` | PyPI | From 4.17.0 | 4.17.1 |
| `pretix` | PyPI | From 4.17.0 | 4.17.1 |

Products: Rami Pretix.

## How do I fix CVE-2023-27891?

Upgrade pretix to a fixed version for your release line: 4.15.1, 4.17.1 or 4.16.1.

## Is CVE-2023-27891 being exploited?

There is no known exploitation of CVE-2023-27891 in the wild and no public exploit code.

## Other vulnerabilities in n/a

- [CVE-2023-44464](https://insights.sbomify.com/CVE-2023-44464/): pretix allows Pillow to parse EPS files (high 7.8)
- [CVE-2023-44463](https://insights.sbomify.com/CVE-2023-44463/): pretix potential IP address spoofing vulnerability (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-27891 and fix it if it is affected.

What it is: CVE-2023-27891 is a high-severity authentication bypass vulnerability in n/a, published on 6 Mar 2023. 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-2023-27891 in the wild and no public exploit code.

Affected packages and fixed versions:
- pretix (PyPI): affected all versions; fixed in 4.15.1
- pretix (PyPI): affected all versions; fixed in 4.15.1
- pretix (PyPI): affected all versions; fixed in 4.17.1
- pretix (PyPI): affected from 4.16.0; fixed in 4.16.1
- pretix (PyPI): affected from 4.16.0; fixed in 4.16.1
- pretix (PyPI): affected from 4.17.0; fixed in 4.17.1
- pretix (PyPI): affected from 4.17.0; fixed in 4.17.1

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-2023-27891/ (Markdown: https://insights.sbomify.com/CVE-2023-27891/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-27891
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-27891
- OSV: https://osv.dev/vulnerability/CVE-2023-27891

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-27891/
Summaries are generated and may contain mistakes; the official description above is the record.