# CVE-2026-49844: log4j: Improper encoding of non-finite floating-point values during MapMessage JSON serialization in Apache Log4j API produc...

CVE-2026-49844 is fixed in 3 products on 1 platform, first by ALAS2023-2026-2072, released August 31, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-49844
- Priority: Routine
- CVSS: n/a (moderate)
- EPSS: 0.0060
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Aug 31, 2026

## Description

Improper encoding of non-finite floating-point values during MapMessage JSON serialization in Apache Log4j API produces output that is not valid JSON. This issue affects Apache Log4j API versions 2.13.1 through 2.25.4 and version 2.26.0.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | log4j amzn 2023 | 2.17.2-1.amzn2023.0.6 | [ALAS2023-2026-2072](https://patchblox.com/security/data/fix/linux/alas2023-2026-2072.md) | Aug 31, 2026 |
| Linux | log4j-jcl amzn 2023 | 2.17.2-1.amzn2023.0.6 | [ALAS2023-2026-2072](https://patchblox.com/security/data/fix/linux/alas2023-2026-2072.md) | Aug 31, 2026 |
| Linux | log4j-slf4j amzn 2023 | 2.17.2-1.amzn2023.0.6 | [ALAS2023-2026-2072](https://patchblox.com/security/data/fix/linux/alas2023-2026-2072.md) | Aug 31, 2026 |

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Data as of 2026-11-11T13:47:35Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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