# CVE-2026-31535: linux: In the Linux kernel, the following vulnerability has been resolved:  smb: client: make use of smbdirect_socket.recv_i...

CVE-2026-31535 is fixed in 23 products on 1 platform, first by ALAS2023-2026-1514, released March 30, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-31535
- Priority: Routine
- CVSS: 4.7 (medium)
- EPSS: 0.0009
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Mar 30, 2026

## Description

In the Linux kernel, the following vulnerability has been resolved:  smb: client: make use of smbdirect_socket.recv_io.credits.available  The logic off managing recv credits by counting posted recv_io and granted credits is racy.  That's because the peer might already consumed a credit, but between receiving the incoming recv at the hardware and processing the completion in the 'recv_done' functions we likely have a window where we grant credits, which don't really exist.  So we better have a decicated counter for the available credits, which will be incremented when we posted new recv buffers and drained when we grant the credits to the peer.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | bpftool6.18 amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | bpftool6.18-debuginfo amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | kernel-livepatch-6.18.15-14.217 amzn 2023 | 1:1.0-0.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | kernel6.18 amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | kernel6.18-debuginfo amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | kernel6.18-debuginfo-common-aarch64 amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | kernel6.18-debuginfo-common-x86_64 amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | kernel6.18-devel amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | kernel6.18-headers amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | kernel6.18-libbpf amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | kernel6.18-libbpf-debuginfo amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | kernel6.18-libbpf-devel amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | kernel6.18-libbpf-static amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | kernel6.18-modules-extra amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | kernel6.18-modules-extra-common amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | kernel6.18-tools amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | kernel6.18-tools-debuginfo amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | kernel6.18-tools-devel amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | linux Debian 14 | 6.18.12-1 | [DEBIAN-CVE-2026-31535](https://patchblox.com/security/data/fix/linux/debian-cve-2026-31535.md) | May 15, 2026 |
| Linux | perf6.18 amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | perf6.18-debuginfo amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | python3-perf6.18 amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |
| Linux | python3-perf6.18-debuginfo amzn 2023 | 1:6.18.15-14.217.amzn2023 | [ALAS2023-2026-1514](https://patchblox.com/security/data/fix/linux/alas2023-2026-1514.md) | Mar 30, 2026 |

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Data as of 2026-11-09T01:18:40Z 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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