# CVE-2026-42926: nginx: When NGINX Open Source is configured to proxy HTTP/2 traffic by setting proxy_http_version to 2, and also uses proxy_...

CVE-2026-42926 is fixed in 18 products on 1 platform, first by ALAS2023-2026-1714, released May 25, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-42926
- Priority: High
- CVSS: n/a (important)
- EPSS: 0.0035
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: May 13, 2026

## Description

When NGINX Open Source is configured to proxy HTTP/2 traffic by setting proxy_http_version to 2, and also uses proxy_set_body, an attacker may be able to inject frame headers and payload bytes to the upstream peer.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | nginx Debian 14 | 1.30.0-4 | [DEBIAN-CVE-2026-42926](https://patchblox.com/security/data/fix/linux/debian-cve-2026-42926.md) | May 27, 2026 |
| Linux | nginx amzn 2023 | 1:1.30.1-1.amzn2023.0.1 | [ALAS2023-2026-1714](https://patchblox.com/security/data/fix/linux/alas2023-2026-1714.md) | May 25, 2026 |
| Linux | nginx-all-modules amzn 2023 | 1:1.30.1-1.amzn2023.0.1 | [ALAS2023-2026-1714](https://patchblox.com/security/data/fix/linux/alas2023-2026-1714.md) | May 25, 2026 |
| Linux | nginx-core amzn 2023 | 1:1.30.1-1.amzn2023.0.1 | [ALAS2023-2026-1714](https://patchblox.com/security/data/fix/linux/alas2023-2026-1714.md) | May 25, 2026 |
| Linux | nginx-core-debuginfo amzn 2023 | 1:1.30.1-1.amzn2023.0.1 | [ALAS2023-2026-1714](https://patchblox.com/security/data/fix/linux/alas2023-2026-1714.md) | May 25, 2026 |
| Linux | nginx-debuginfo amzn 2023 | 1:1.30.1-1.amzn2023.0.1 | [ALAS2023-2026-1714](https://patchblox.com/security/data/fix/linux/alas2023-2026-1714.md) | May 25, 2026 |
| Linux | nginx-debugsource amzn 2023 | 1:1.30.1-1.amzn2023.0.1 | [ALAS2023-2026-1714](https://patchblox.com/security/data/fix/linux/alas2023-2026-1714.md) | May 25, 2026 |
| Linux | nginx-filesystem amzn 2023 | 1:1.30.1-1.amzn2023.0.1 | [ALAS2023-2026-1714](https://patchblox.com/security/data/fix/linux/alas2023-2026-1714.md) | May 25, 2026 |
| Linux | nginx-mod-devel amzn 2023 | 1:1.30.1-1.amzn2023.0.1 | [ALAS2023-2026-1714](https://patchblox.com/security/data/fix/linux/alas2023-2026-1714.md) | May 25, 2026 |
| Linux | nginx-mod-http-image-filter amzn 2023 | 1:1.30.1-1.amzn2023.0.1 | [ALAS2023-2026-1714](https://patchblox.com/security/data/fix/linux/alas2023-2026-1714.md) | May 25, 2026 |
| Linux | nginx-mod-http-image-filter-debuginfo amzn 2023 | 1:1.30.1-1.amzn2023.0.1 | [ALAS2023-2026-1714](https://patchblox.com/security/data/fix/linux/alas2023-2026-1714.md) | May 25, 2026 |
| Linux | nginx-mod-http-perl amzn 2023 | 1:1.30.1-1.amzn2023.0.1 | [ALAS2023-2026-1714](https://patchblox.com/security/data/fix/linux/alas2023-2026-1714.md) | May 25, 2026 |
| Linux | nginx-mod-http-perl-debuginfo amzn 2023 | 1:1.30.1-1.amzn2023.0.1 | [ALAS2023-2026-1714](https://patchblox.com/security/data/fix/linux/alas2023-2026-1714.md) | May 25, 2026 |
| Linux | nginx-mod-http-xslt-filter amzn 2023 | 1:1.30.1-1.amzn2023.0.1 | [ALAS2023-2026-1714](https://patchblox.com/security/data/fix/linux/alas2023-2026-1714.md) | May 25, 2026 |
| Linux | nginx-mod-http-xslt-filter-debuginfo amzn 2023 | 1:1.30.1-1.amzn2023.0.1 | [ALAS2023-2026-1714](https://patchblox.com/security/data/fix/linux/alas2023-2026-1714.md) | May 25, 2026 |
| Linux | nginx-mod-mail amzn 2023 | 1:1.30.1-1.amzn2023.0.1 | [ALAS2023-2026-1714](https://patchblox.com/security/data/fix/linux/alas2023-2026-1714.md) | May 25, 2026 |
| Linux | nginx-mod-mail-debuginfo amzn 2023 | 1:1.30.1-1.amzn2023.0.1 | [ALAS2023-2026-1714](https://patchblox.com/security/data/fix/linux/alas2023-2026-1714.md) | May 25, 2026 |
| Linux | nginx-mod-stream amzn 2023 | 1:1.30.1-1.amzn2023.0.1 | [ALAS2023-2026-1714](https://patchblox.com/security/data/fix/linux/alas2023-2026-1714.md) | May 25, 2026 |
| Linux | nginx-mod-stream-debuginfo amzn 2023 | 1:1.30.1-1.amzn2023.0.1 | [ALAS2023-2026-1714](https://patchblox.com/security/data/fix/linux/alas2023-2026-1714.md) | May 25, 2026 |

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Data as of 2026-11-08T13:06:02Z 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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