# CVE-2021-3690: undertow: A flaw was found in Undertow

CVE-2021-3690 is fixed in undertow on 1 platform by DEBIAN-CVE-2021-3690 (version 2.2.10-1), released August 23, 2022. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2021-3690
- Priority: High
- CVSS: 7.5 (high)
- EPSS: 0.0177
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 23, 2022

## Description

A flaw was found in Undertow. A buffer leak on the incoming WebSocket PONG message may lead to memory exhaustion. This flaw allows an attacker to cause a denial of service. The highest threat from this vulnerability is availability.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | undertow Debian 14 | 2.2.10-1 | [DEBIAN-CVE-2021-3690](https://patchblox.com/security/data/fix/linux/debian-cve-2021-3690.md) | Aug 23, 2022 |

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