# CVE-2026-90143: net: kcm: Hold RCU read lock while running BPF parser

CVE-2026-90143 is fixed in 2 products on 1 platform, first by DEBIAN-CVE-2026-90143, released September 23, 2026. It is not reported as exploited. Patch Radar priority: High.

- Web page: https://patchblox.com/security/cve/CVE-2026-90143
- Priority: High
- CVSS: 7.8 (Moderate)
- EPSS: 0.0016
- 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-2026-90143

## Description

In the Linux kernel, the following vulnerability has been resolved:  net: kcm: Hold RCU read lock while running BPF parser  kcm_parse_func_strparser() calls bpf_prog_run_pin_on_cpu() which prevents CPU migration, but does not establish an RCU read-side critical section. Consequently, BPF map operations can trigger WARN_ON_ONCE(!bpf_rcu_lock_held()) when called from the KCM strparser program.  Hold the RCU read lock while running the program.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | linux Debian 12.15 (bookworm) | 6.1.190-1 | [DEBIAN-CVE-2026-90143](https://patchblox.com/security/data/fix/linux/debian-cve-2026-90143.md) | Sep 23, 2026 |
| Linux | linux Debian 13.5 (trixie) | 6.12.111-1 | [DEBIAN-CVE-2026-90143](https://patchblox.com/security/data/fix/linux/debian-cve-2026-90143.md) | Sep 23, 2026 |
| Linux | linux Debian 14 | 7.2.6-1 | [DEBIAN-CVE-2026-90143](https://patchblox.com/security/data/fix/linux/debian-cve-2026-90143.md) | Sep 23, 2026 |
| Linux | linux-6.12 Debian 12.15 (bookworm) | 6.12.111-1~deb12u1 | [DEBIAN-CVE-2026-90143](https://patchblox.com/security/data/fix/linux/debian-cve-2026-90143.md) | Sep 23, 2026 |

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Data as of 2026-11-08T06:59:42Z 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 Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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