# CVE-2026-98394: af_unix: Return immediately when manage_oob() returns NULL for 0-length buffer.

CVE-2026-98394 is fixed in 38 products on 1 platform, first by DEBIAN-CVE-2026-98394, released October 16, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-98394
- Priority: Routine
- CVSS: 2.5 (Low)
- EPSS: 0.0020
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Oct 12, 2026
- Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-98394

## Description

In the Linux kernel, the following vulnerability has been resolved:  af_unix: Return immediately when manage_oob() returns NULL for 0-length buffer.  Fahad Alharbi reported that recv(0, MSG_PEEK) triggers busy-wait in unix_stream_read_generic() if recv() is blocking and the last skb in the queue is MSG_OOB skb.  In such a situation, TCP returns 0 immediately regardless of blocking or non-blocking.  Let's follow the behaviour.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | bpftool6.12 amzn 2023 | 1:6.12.111-136.204.amzn2023 | [ALAS2023-2026-3193](https://patchblox.com/security/data/fix/linux/alas2023-2026-3193.md) | Nov 7, 2026 |
| Linux | bpftool6.12-debuginfo amzn 2023 | 1:6.12.111-136.204.amzn2023 | [ALAS2023-2026-3193](https://patchblox.com/security/data/fix/linux/alas2023-2026-3193.md) | Nov 7, 2026 |
| Linux | bpftool6.18 amzn 2023 | 1:6.18.54-121.166.amzn2023 | [ALAS2023-2026-3192](https://patchblox.com/security/data/fix/linux/alas2023-2026-3192.md) | Nov 7, 2026 |
| Linux | bpftool6.18-debuginfo amzn 2023 | 1:6.18.54-121.166.amzn2023 | [ALAS2023-2026-3192](https://patchblox.com/security/data/fix/linux/alas2023-2026-3192.md) | Nov 7, 2026 |
| Linux | kernel-livepatch-6.12.111-136.204 amzn 2023 | 1:1.0-0.amzn2023 | [ALAS2023-2026-3193](https://patchblox.com/security/data/fix/linux/alas2023-2026-3193.md) | Nov 7, 2026 |
| Linux | kernel-livepatch-6.18.54-121.166 amzn 2023 | 1:1.0-0.amzn2023 | [ALAS2023-2026-3192](https://patchblox.com/security/data/fix/linux/alas2023-2026-3192.md) | Nov 7, 2026 |
| Linux | kernel6.12 amzn 2023 | 1:6.12.111-136.204.amzn2023 | [ALAS2023-2026-3193](https://patchblox.com/security/data/fix/linux/alas2023-2026-3193.md) | Nov 7, 2026 |
| Linux | kernel6.12-debuginfo amzn 2023 | 1:6.12.111-136.204.amzn2023 | [ALAS2023-2026-3193](https://patchblox.com/security/data/fix/linux/alas2023-2026-3193.md) | Nov 7, 2026 |
| Linux | kernel6.12-debuginfo-common-aarch64 amzn 2023 | 1:6.12.111-136.204.amzn2023 | [ALAS2023-2026-3193](https://patchblox.com/security/data/fix/linux/alas2023-2026-3193.md) | Nov 7, 2026 |
| Linux | kernel6.12-debuginfo-common-x86_64 amzn 2023 | 1:6.12.111-136.204.amzn2023 | [ALAS2023-2026-3193](https://patchblox.com/security/data/fix/linux/alas2023-2026-3193.md) | Nov 7, 2026 |
| Linux | kernel6.12-devel amzn 2023 | 1:6.12.111-136.204.amzn2023 | [ALAS2023-2026-3193](https://patchblox.com/security/data/fix/linux/alas2023-2026-3193.md) | Nov 7, 2026 |
| Linux | kernel6.12-headers amzn 2023 | 1:6.12.111-136.204.amzn2023 | [ALAS2023-2026-3193](https://patchblox.com/security/data/fix/linux/alas2023-2026-3193.md) | Nov 7, 2026 |
| Linux | kernel6.12-modules-extra amzn 2023 | 1:6.12.111-136.204.amzn2023 | [ALAS2023-2026-3193](https://patchblox.com/security/data/fix/linux/alas2023-2026-3193.md) | Nov 7, 2026 |
| Linux | kernel6.12-modules-extra-common amzn 2023 | 1:6.12.111-136.204.amzn2023 | [ALAS2023-2026-3193](https://patchblox.com/security/data/fix/linux/alas2023-2026-3193.md) | Nov 7, 2026 |
| Linux | kernel6.12-tools amzn 2023 | 1:6.12.111-136.204.amzn2023 | [ALAS2023-2026-3193](https://patchblox.com/security/data/fix/linux/alas2023-2026-3193.md) | Nov 7, 2026 |
| Linux | kernel6.12-tools-debuginfo amzn 2023 | 1:6.12.111-136.204.amzn2023 | [ALAS2023-2026-3193](https://patchblox.com/security/data/fix/linux/alas2023-2026-3193.md) | Nov 7, 2026 |
| Linux | kernel6.12-tools-devel amzn 2023 | 1:6.12.111-136.204.amzn2023 | [ALAS2023-2026-3193](https://patchblox.com/security/data/fix/linux/alas2023-2026-3193.md) | Nov 7, 2026 |
| Linux | kernel6.18 amzn 2023 | 1:6.18.54-121.166.amzn2023 | [ALAS2023-2026-3192](https://patchblox.com/security/data/fix/linux/alas2023-2026-3192.md) | Nov 7, 2026 |
| Linux | kernel6.18-debuginfo amzn 2023 | 1:6.18.54-121.166.amzn2023 | [ALAS2023-2026-3192](https://patchblox.com/security/data/fix/linux/alas2023-2026-3192.md) | Nov 7, 2026 |
| Linux | kernel6.18-debuginfo-common-aarch64 amzn 2023 | 1:6.18.54-121.166.amzn2023 | [ALAS2023-2026-3192](https://patchblox.com/security/data/fix/linux/alas2023-2026-3192.md) | Nov 7, 2026 |
| Linux | kernel6.18-debuginfo-common-x86_64 amzn 2023 | 1:6.18.54-121.166.amzn2023 | [ALAS2023-2026-3192](https://patchblox.com/security/data/fix/linux/alas2023-2026-3192.md) | Nov 7, 2026 |
| Linux | kernel6.18-devel amzn 2023 | 1:6.18.54-121.166.amzn2023 | [ALAS2023-2026-3192](https://patchblox.com/security/data/fix/linux/alas2023-2026-3192.md) | Nov 7, 2026 |
| Linux | kernel6.18-headers amzn 2023 | 1:6.18.54-121.166.amzn2023 | [ALAS2023-2026-3192](https://patchblox.com/security/data/fix/linux/alas2023-2026-3192.md) | Nov 7, 2026 |
| Linux | kernel6.18-modules-extra amzn 2023 | 1:6.18.54-121.166.amzn2023 | [ALAS2023-2026-3192](https://patchblox.com/security/data/fix/linux/alas2023-2026-3192.md) | Nov 7, 2026 |
| Linux | kernel6.18-modules-extra-common amzn 2023 | 1:6.18.54-121.166.amzn2023 | [ALAS2023-2026-3192](https://patchblox.com/security/data/fix/linux/alas2023-2026-3192.md) | Nov 7, 2026 |
| Linux | kernel6.18-tools amzn 2023 | 1:6.18.54-121.166.amzn2023 | [ALAS2023-2026-3192](https://patchblox.com/security/data/fix/linux/alas2023-2026-3192.md) | Nov 7, 2026 |
| Linux | kernel6.18-tools-debuginfo amzn 2023 | 1:6.18.54-121.166.amzn2023 | [ALAS2023-2026-3192](https://patchblox.com/security/data/fix/linux/alas2023-2026-3192.md) | Nov 7, 2026 |
| Linux | kernel6.18-tools-devel amzn 2023 | 1:6.18.54-121.166.amzn2023 | [ALAS2023-2026-3192](https://patchblox.com/security/data/fix/linux/alas2023-2026-3192.md) | Nov 7, 2026 |
| Linux | linux Debian 13.5 (trixie) | 6.12.111-1 | [DEBIAN-CVE-2026-98394](https://patchblox.com/security/data/fix/linux/debian-cve-2026-98394.md) | Oct 16, 2026 |
| Linux | linux Debian 14 | 7.2.7-1 | [DEBIAN-CVE-2026-98394](https://patchblox.com/security/data/fix/linux/debian-cve-2026-98394.md) | Oct 16, 2026 |
| Linux | microvm-kernel6.18 amzn 2023 | 1:6.18.54-121.166.amzn2023 | [ALAS2023-2026-3192](https://patchblox.com/security/data/fix/linux/alas2023-2026-3192.md) | Nov 7, 2026 |
| Linux | perf6.12 amzn 2023 | 1:6.12.111-136.204.amzn2023 | [ALAS2023-2026-3193](https://patchblox.com/security/data/fix/linux/alas2023-2026-3193.md) | Nov 7, 2026 |
| Linux | perf6.12-debuginfo amzn 2023 | 1:6.12.111-136.204.amzn2023 | [ALAS2023-2026-3193](https://patchblox.com/security/data/fix/linux/alas2023-2026-3193.md) | Nov 7, 2026 |
| Linux | perf6.18 amzn 2023 | 1:6.18.54-121.166.amzn2023 | [ALAS2023-2026-3192](https://patchblox.com/security/data/fix/linux/alas2023-2026-3192.md) | Nov 7, 2026 |
| Linux | perf6.18-debuginfo amzn 2023 | 1:6.18.54-121.166.amzn2023 | [ALAS2023-2026-3192](https://patchblox.com/security/data/fix/linux/alas2023-2026-3192.md) | Nov 7, 2026 |
| Linux | python3-perf6.12 amzn 2023 | 1:6.12.111-136.204.amzn2023 | [ALAS2023-2026-3193](https://patchblox.com/security/data/fix/linux/alas2023-2026-3193.md) | Nov 7, 2026 |
| Linux | python3-perf6.12-debuginfo amzn 2023 | 1:6.12.111-136.204.amzn2023 | [ALAS2023-2026-3193](https://patchblox.com/security/data/fix/linux/alas2023-2026-3193.md) | Nov 7, 2026 |
| Linux | python3-perf6.18 amzn 2023 | 1:6.18.54-121.166.amzn2023 | [ALAS2023-2026-3192](https://patchblox.com/security/data/fix/linux/alas2023-2026-3192.md) | Nov 7, 2026 |
| Linux | python3-perf6.18-debuginfo amzn 2023 | 1:6.18.54-121.166.amzn2023 | [ALAS2023-2026-3192](https://patchblox.com/security/data/fix/linux/alas2023-2026-3192.md) | Nov 7, 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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