# Multiple Linux kernel vulnerabilities in Ubuntu

Published: 2026-09-04 · Severity: routine
Canonical: https://vorant.io/reports/aefda27a-8bd0-5a02-91db-e16aa59a6579/multiple-linux-kernel-vulnerabilities-in-ubuntu

> Multiple unspecified vulnerabilities in Ubuntu Linux kernel affect 18.04 and 20.04 ESM; patches available.

CERT-FR reports multiple vulnerabilities discovered in the Linux kernel used by Ubuntu 18.04 ESM and 20.04 ESM. The specific attack vectors and impacts are not detailed by Ubuntu in the advisory, with the vendor only stating that attackers could provoke an unspecified security problem. Ubuntu has released kernel security updates across three bulletins (USN-8661-4, USN-8714-1, and USN-8715-1) dated 2 September 2026 to address 40 distinct CVEs in the kernel. These are primarily patched vulnerabilities with no indication of active exploitation in the wild at the time of the advisory. Defenders should prioritize applying kernel updates to affected ESM systems, as kernel vulnerabilities can enable privilege escalation, local denial of service, or information disclosure depending on the individual CVE details.

## Mentioned in this report

- Vulnerabilities: CVE-2021-47378, CVE-2025-27558, CVE-2026-23392, CVE-2026-31405, CVE-2026-31414, CVE-2026-31448, CVE-2026-31657, CVE-2026-31668, CVE-2026-31705, CVE-2026-43071, CVE-2026-43198, CVE-2026-43378, CVE-2026-43493, CVE-2026-43499, CVE-2026-46266, CVE-2026-46331, CVE-2026-52914, CVE-2026-52924, CVE-2026-52931, CVE-2026-52955, CVE-2026-52958, CVE-2026-52982, CVE-2026-52986, CVE-2026-52989, CVE-2026-52993, CVE-2026-52999, CVE-2026-53002, CVE-2026-53006, CVE-2026-53043, CVE-2026-53045, CVE-2026-53086, CVE-2026-53088, CVE-2026-53176, CVE-2026-53212, CVE-2026-53215, CVE-2026-53224, CVE-2026-53225, CVE-2026-53228, CVE-2026-53246, CVE-2026-53309

Source reporting: https://www.cert.ssi.gouv.fr/avis/CERTFR-2026-AVI-1117

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