# CVE-2021-34337: mailman3: An issue was discovered in Mailman Core before 3.3.5

CVE-2021-34337 is fixed in mailman3 on 1 platform, first by DEBIAN-CVE-2021-34337, released April 15, 2023. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-34337
- Priority: Routine
- CVSS: 6.3 (medium)
- EPSS: 0.0030
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Apr 15, 2023

## Description

An issue was discovered in Mailman Core before 3.3.5. An attacker with access to the REST API could use timing attacks to determine the value of the configured REST API password and then make arbitrary REST API calls. The REST API is bound to localhost by default, limiting the ability for attackers to exploit this, but can optionally be made to listen on other interfaces.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | mailman3 Debian 12.15 (bookworm) | 3.3.7-1 | [DEBIAN-CVE-2021-34337](https://patchblox.com/security/data/fix/linux/debian-cve-2021-34337.md) | Apr 15, 2023 |
| Linux | mailman3 Debian 13.5 (trixie) | 3.3.7-1 | [DEBIAN-CVE-2021-34337](https://patchblox.com/security/data/fix/linux/debian-cve-2021-34337.md) | Apr 15, 2023 |
| Linux | mailman3 Debian 14 | 3.3.7-1 | [DEBIAN-CVE-2021-34337](https://patchblox.com/security/data/fix/linux/debian-cve-2021-34337.md) | Apr 15, 2023 |

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Data as of 2026-11-08T06:59:42Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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