# CVE-2020-22284: liblwip0: A buffer overflow vulnerability in the zepif_linkoutput() function of Free Software Foundation lwIP git head version...

CVE-2020-22284 is fixed in liblwip0 on 1 platform by liblwip0 2.1.2+dfsg1-4ubuntu0.1~esm1 (version 2.1.2+dfsg1-4ubuntu0.1~esm1), released May 18, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2020-22284
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0122
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Jul 22, 2021

## Description

A buffer overflow vulnerability in the zepif_linkoutput() function of Free Software Foundation lwIP git head version and version 2.1.2 allows attackers to access sensitive information via a crafted 6LoWPAN packet.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | liblwip0 Ubuntu 20.04 LTS (focal) | 2.1.2+dfsg1-4ubuntu0.1~esm1 | [liblwip0 2.1.2+dfsg1-4ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-liblwip0-2.1.2-dfsg1-4ubuntu0.1-esm1.md) | May 18, 2026 |

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Data as of 2026-11-08T00:53:09Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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