# CVE-2026-90077: net: fix a resource leak in copy_net_ns() error handling path CVE-2026-90077 is fixed in 20 products on 1 platform, first by DEBIAN-CVE-2026-90077, released September 23, 2026. It is not reported as exploited. Patch Radar priority: High. - Web page: https://patchblox.com/security/cve/CVE-2026-90077 - Priority: High - CVSS: n/a (important) - EPSS: 0.0021 - CISA KEV: not listed - Exploited (vendor report): no - Publicly disclosed: no - Published: Sep 17, 2026 - Vendor advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-90077 ## Description In the Linux kernel, the following vulnerability has been resolved: net: fix a resource leak in copy_net_ns() error handling path Currently, preinit_net() does two things: (1) call ns_common_init() which might fail (2) initialize resources which does not fail However, preinit_net() is returning early when (1) fails, and copy_net_ns() is jumping to the dec_ucounts: label. As a result, resources allocated by net_alloc() are leaking. We need to call key_remove_domain() and net_passive_dec() in order to release resources allocated by net_alloc(). We cannot simply jump to the put_userns: label when preinit_net() failed, for (2) is not yet done. But we can reorder (1) and (2), for there is no dependency between (1) and (2). Therefore, this patch decouples (1) from preinit_net() and changes preinit_net() back to a void function, and calls ns_common_init() after preinit_net() succeeded. Then, we can jump to immediately after ns_common_free() of the put_userns: label. ## Where it's fixed | Platform | Product | Fixed in | Fix | Released | |---|---|---|---|---| | 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-6.18.54-121.166 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 | kernel6.18 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 14 | 7.2.6-1 | [DEBIAN-CVE-2026-90077](https://patchblox.com/security/data/fix/linux/debian-cve-2026-90077.md) | Sep 23, 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 | perf6.18 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-perf6.18 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 | --- Data as of 2026-11-08T13:06:02Z UTC. 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