# CVE-2026-23918: Apache HTTP Server: http2: double free and possible RCE on early reset

CVE-2026-23918 is fixed in 17 products on 2 platforms, first by apache2 2.4.66-2ubuntu2.1, released May 4, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-23918
- Priority: High
- CVSS: 8.8 (Important)
- EPSS: 0.4973
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: May 4, 2026
- Weakness: Double Free
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23918

## Description

This is a vulnerability in open source code and Apple Software is among the affected projects. The

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| macOS | Sequoia | 15.7.8 | [Sequoia 15.7.8](https://patchblox.com/security/data/fix/macos/sequoia-15.7.8.md) | Jul 27, 2026 |
| macOS | Sonoma | 14.8.8 | [Sonoma 14.8.8](https://patchblox.com/security/data/fix/macos/sonoma-14.8.8.md) | Jul 27, 2026 |
| macOS | Tahoe | 26.6 | [Tahoe 26.6](https://patchblox.com/security/data/fix/macos/tahoe-26.6.md) | Jul 27, 2026 |
| Linux | apache2 Debian 12.15 (bookworm) | 2.4.67-1~deb12u2 | [DEBIAN-CVE-2026-23918](https://patchblox.com/security/data/fix/linux/debian-cve-2026-23918.md) | May 15, 2026 |
| Linux | apache2 Debian 13.5 (trixie) | 2.4.66-1~deb13u2 | [DEBIAN-CVE-2026-23918](https://patchblox.com/security/data/fix/linux/debian-cve-2026-23918.md) | May 15, 2026 |
| Linux | apache2 Debian 14 | 2.4.66-5 | [DEBIAN-CVE-2026-23918](https://patchblox.com/security/data/fix/linux/debian-cve-2026-23918.md) | May 15, 2026 |
| Linux | apache2 Ubuntu 26.04.1 LTS (resolute) | 2.4.66-2ubuntu2.1 | [apache2 2.4.66-2ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-apache2-2.4.66-2ubuntu2.1.md) | May 4, 2026 |
| Linux | apache2 opensuse-leap 16.0 | 2.4.66-160000.2.1 | [OPENSUSE-SU-2026:21115-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21115-1.md) | Jun 20, 2026 |
| Linux | apache2 sles 16.0 | 2.4.66-160000.2.1 | [SUSE-SU-2026:22209-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22209-1.md) | Jun 20, 2026 |
| Linux | apache2-bin Ubuntu 26.04.1 LTS (resolute) | 2.4.66-2ubuntu2.1 | [apache2-bin 2.4.66-2ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-apache2-bin-2.4.66-2ubuntu2.1.md) | May 4, 2026 |
| Linux | apache2-data Ubuntu 26.04.1 LTS (resolute) | 2.4.66-2ubuntu2.1 | [apache2-data 2.4.66-2ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-apache2-data-2.4.66-2ubuntu2.1.md) | May 4, 2026 |
| Linux | apache2-devel opensuse-leap 16.0 | 2.4.66-160000.2.1 | [OPENSUSE-SU-2026:21115-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21115-1.md) | Jun 20, 2026 |
| Linux | apache2-devel sles 16.0 | 2.4.66-160000.2.1 | [SUSE-SU-2026:22209-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22209-1.md) | Jun 20, 2026 |
| Linux | apache2-event opensuse-leap 16.0 | 2.4.66-160000.2.1 | [OPENSUSE-SU-2026:21115-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21115-1.md) | Jun 20, 2026 |
| Linux | apache2-event sles 16.0 | 2.4.66-160000.2.1 | [SUSE-SU-2026:22209-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22209-1.md) | Jun 20, 2026 |
| Linux | apache2-manual opensuse-leap 16.0 | 2.4.66-160000.2.1 | [OPENSUSE-SU-2026:21115-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21115-1.md) | Jun 20, 2026 |
| Linux | apache2-manual sles 16.0 | 2.4.66-160000.2.1 | [SUSE-SU-2026:22209-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22209-1.md) | Jun 20, 2026 |
| Linux | apache2-prefork opensuse-leap 16.0 | 2.4.66-160000.2.1 | [OPENSUSE-SU-2026:21115-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21115-1.md) | Jun 20, 2026 |
| Linux | apache2-prefork sles 16.0 | 2.4.66-160000.2.1 | [SUSE-SU-2026:22209-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22209-1.md) | Jun 20, 2026 |
| Linux | apache2-suexec-custom Ubuntu 26.04.1 LTS (resolute) | 2.4.66-2ubuntu2.1 | [apache2-suexec-custom 2.4.66-2ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-apache2-suexec-custom-2.4.66-2ubuntu2.1.md) | May 4, 2026 |
| Linux | apache2-suexec-pristine Ubuntu 26.04.1 LTS (resolute) | 2.4.66-2ubuntu2.1 | [apache2-suexec-pristine 2.4.66-2ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-apache2-suexec-pristine-2.4.66-2ubuntu2.1.md) | May 4, 2026 |
| Linux | apache2-utils Ubuntu 26.04.1 LTS (resolute) | 2.4.66-2ubuntu2.1 | [apache2-utils 2.4.66-2ubuntu2.1](https://patchblox.com/security/data/fix/linux/ubuntu-resolute-apache2-utils-2.4.66-2ubuntu2.1.md) | May 4, 2026 |
| Linux | apache2-utils opensuse-leap 16.0 | 2.4.66-160000.2.1 | [OPENSUSE-SU-2026:21115-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21115-1.md) | Jun 20, 2026 |
| Linux | apache2-utils sles 16.0 | 2.4.66-160000.2.1 | [SUSE-SU-2026:22209-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22209-1.md) | Jun 20, 2026 |
| Linux | apache2-worker opensuse-leap 16.0 | 2.4.66-160000.2.1 | [OPENSUSE-SU-2026:21115-1](https://patchblox.com/security/data/fix/linux/opensuse-su-2026-21115-1.md) | Jun 20, 2026 |
| Linux | apache2-worker sles 16.0 | 2.4.66-160000.2.1 | [SUSE-SU-2026:22209-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22209-1.md) | Jun 20, 2026 |
| Linux | mod_http2 amzn 2023 | 2.0.39-1.amzn2023.0.1 | [ALAS2023-2026-1724](https://patchblox.com/security/data/fix/linux/alas2023-2026-1724.md) | May 25, 2026 |
| Linux | mod_http2-debuginfo amzn 2023 | 2.0.39-1.amzn2023.0.1 | [ALAS2023-2026-1724](https://patchblox.com/security/data/fix/linux/alas2023-2026-1724.md) | May 25, 2026 |
| Linux | mod_http2-debugsource amzn 2023 | 2.0.39-1.amzn2023.0.1 | [ALAS2023-2026-1724](https://patchblox.com/security/data/fix/linux/alas2023-2026-1724.md) | May 25, 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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