# CVE-2024-7885: undertow: A vulnerability was found in Undertow where the ProxyProtocolReadListener reuses the same StringBuilder instance acro...

CVE-2024-7885 is fixed in undertow on 1 platform by DEBIAN-CVE-2024-7885 (version 2.3.18-1), released August 21, 2024. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2024-7885
- Priority: High
- CVSS: 7.5 (high)
- EPSS: 0.0264
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 21, 2024

## Description

A vulnerability was found in Undertow where the ProxyProtocolReadListener reuses the same StringBuilder instance across multiple requests. This issue occurs when the parseProxyProtocolV1 method processes multiple requests on the same HTTP connection. As a result, different requests may share the same StringBuilder instance, potentially leading to information leakage between requests or responses. In some cases, a value from a previous request or response may be erroneously reused, which could lead to unintended data exposure. This issue primarily results in errors and connection termination but creates a risk of data leakage in multi-request environments.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | undertow Debian 14 | 2.3.18-1 | [DEBIAN-CVE-2024-7885](https://patchblox.com/security/data/fix/linux/debian-cve-2024-7885.md) | Aug 21, 2024 |

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