# CVE-2026-23437: linux: In the Linux kernel, the following vulnerability has been resolved: net: shaper: protect late read accesses to the h... CVE-2026-23437 is fixed in 27 products on 1 platform, first by DEBIAN-CVE-2026-23437, released April 3, 2026. It is not reported as exploited. Patch Radar priority: Routine. - Web page: https://patchblox.com/security/cve/CVE-2026-23437 - Priority: Routine - CVSS: 5.5 (medium) - EPSS: 0.0013 - CISA KEV: not listed - Exploited (vendor report): no - Publicly disclosed: no - Published: Apr 3, 2026 ## Description In the Linux kernel, the following vulnerability has been resolved: net: shaper: protect late read accesses to the hierarchy We look up a netdev during prep of Netlink ops (pre- callbacks) and take a ref to it. Then later in the body of the callback we take its lock or RCU which are the actual protections. This is not proper, a conversion from a ref to a locked netdev must include a liveness check (a check if the netdev hasn't been unregistered already). Fix the read cases (those under RCU). Writes needs a separate change to protect from creating the hierarchy after flush has already run. ## Where it's fixed | Platform | Product | Fixed in | Fix | Released | |---|---|---|---|---| | Linux | bpftool6.18 amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | bpftool6.18-debuginfo amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | kernel-livepatch-6.18.20-20.229 amzn 2023 | 1:1.0-0.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | kernel-livepatch-SLE16_Update_10 sles 16.0 | 2-160000.1.1 | [SUSE-SU-2026:22037-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22037-1.md) | Jun 2, 2026 | | Linux | kernel-livepatch-SLE16_Update_11 sles 16.0 | 2-160000.1.1 | [SUSE-SU-2026:22036-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22036-1.md) | Jun 2, 2026 | | Linux | kernel-livepatch-SLE16_Update_8 sles 16.0 | 3-160000.1.1 | [SUSE-SU-2026:22034-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22034-1.md) | Jun 2, 2026 | | Linux | kernel-livepatch-SLE16_Update_9 sles 16.0 | 2-160000.1.1 | [SUSE-SU-2026:22029-1](https://patchblox.com/security/data/fix/linux/suse-su-2026-22029-1.md) | Jun 1, 2026 | | Linux | kernel6.18 amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | kernel6.18-debuginfo amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | kernel6.18-debuginfo-common-aarch64 amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | kernel6.18-debuginfo-common-x86_64 amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | kernel6.18-devel amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | kernel6.18-headers amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | kernel6.18-libbpf amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | kernel6.18-libbpf-debuginfo amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | kernel6.18-libbpf-devel amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | kernel6.18-libbpf-static amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | kernel6.18-modules-extra amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | kernel6.18-modules-extra-common amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | kernel6.18-tools amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | kernel6.18-tools-debuginfo amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | kernel6.18-tools-devel amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | linux Debian 14 | 6.19.10-1 | [DEBIAN-CVE-2026-23437](https://patchblox.com/security/data/fix/linux/debian-cve-2026-23437.md) | Apr 3, 2026 | | Linux | perf6.18 amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | perf6.18-debuginfo amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | python3-perf6.18 amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | | Linux | python3-perf6.18-debuginfo amzn 2023 | 1:6.18.20-20.229.amzn2023 | [ALAS2023-2026-1596](https://patchblox.com/security/data/fix/linux/alas2023-2026-1596.md) | Apr 27, 2026 | --- Data as of 2026-11-09T07:25:28Z UTC. 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