USN-8666-2: Linux kernel (Azure) vulnerabilities
Siebe Devroe, Héloïse Gollier, and Mathy Vanhoef discovered that the WiFi implementation in the Linux kernel did not properly handle aggregated frames in mesh networks, due to an incorrect fix for CVE-2020-24588. A physically proximate attacker could use this issue to inject packets. (CVE-2025-27558) Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - x86 architecture; - Cryptographic API; - InfiniBand drivers; - Media drivers; - NVIDIA Tegra memory controller driver; - Network drivers; - NVME drivers; - File systems infrastructure; - Ext4 file system; - IPv4 networking; - Network traffic control; - TCP network protocol; - Locking primitives; - B.A.T.M.A.N. meshing protocol; - Ceph Core library; - IPv6 networking; - Multipath TCP; - Netfilter; - SCTP protocol; - SMC sockets; - TIPC protocol; (CVE-2021-47378, CVE-2026-23392, CVE-2026-31405, CVE-2026-31414, CVE-2026-31448, CVE-2026-31657, CVE-2026-31668, CVE-2026-43071, CVE-2026-43198, 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-2026-53045, CVE-2026-53088, CVE-2026-53176, CVE-2026-53212, CVE-2026-53228, CVE-2026-53359)
CSIRTS triage
- What
- Multiple vulnerabilities in the Linux kernel including improper handling of WiFi mesh network frames and flaws across numerous subsystems.
- Who is affected
- Systems running Linux kernel versions affected by CVE-2025-27558 and related CVEs across x86, networking, storage, and file system components.
- Urgency
- Multiple kernel vulnerabilities spanning critical subsystems including network packet injection require immediate patching to prevent exploitation.
- Action
- Update the Linux kernel on Azure-managed systems using the provided USN-8666-2 patch.
AI-assisted analysis generated from the source advisory — verify against the original.
⚡ Watch Linux
Get an email when a new Linux advisory drops — max one per day, one-click unsubscribe.
Details
Original advisory: https://ubuntu.com/security/notices/USN-8666-2
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Moderate exploitation riskCVE-2020-245883.5% 30-day exploitation probability. Patch within normal cadence, watch for KEV listing. Riskier than 88% of all EPSS-scored CVEs.
- Low exploitation riskCVE-2025-275580.29% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 21% of all EPSS-scored CVEs.
- Moderate exploitation riskCVE-2021-473781.2% 30-day exploitation probability. Patch within normal cadence, watch for KEV listing. Riskier than 65% of all EPSS-scored CVEs.
- Low exploitation riskCVE-2026-233920.12% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 2% of all EPSS-scored CVEs.
- Low exploitation riskCVE-2026-314050.55% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 44% of all EPSS-scored CVEs.
- Low exploitation riskCVE-2026-314140.40% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 33% of all EPSS-scored CVEs.
- Low exploitation riskCVE-2026-314480.44% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 37% of all EPSS-scored CVEs.
- Low exploitation riskCVE-2026-316570.40% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 33% of all EPSS-scored CVEs.
- Low exploitation riskCVE-2026-316680.44% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 37% of all EPSS-scored CVEs.
- Low exploitation riskCVE-2026-430710.39% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 32% of all EPSS-scored CVEs.
Referenced CVEs
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
- unknownUSN-8630-5: Linux kernel (Raspberry Pi) vulnerabilitiesubuntu
- high[UPDATE] [high] Linux Kernel: Multiple vulnerabilitiescert-bund
- medium[UPDATE] [medium] Linux Kernel: Multiple Vulnerabilitiescert-bund
- medium[UPDATE] [medium] Linux Kernel: Multiple Vulnerabilitiescert-bund
- high[UPDATE] [high] Linux Kernel: Multiple vulnerabilitiescert-bund
- high[UPDATE] [high] Linux Kernel: Vulnerability allows privilege escalationcert-bund
- high[UPDATE] [high] Linux Kernel: Multiple vulnerabilitiescert-bund
- high[UPDATE] [medium] Linux Kernel: Vulnerability Allows Unspecified Attackcert-bund
- low[UPDATE] [low] Linux Kernel: Multiple Vulnerabilities Allow Denial of Servicecert-bund
- medium[UPDATE] [medium] Linux Kernel: Multiple Vulnerabilitiescert-bund
- high[UPDATE] [high] Linux Kernel: Multiple Vulnerabilitiescert-bund
- medium[NEW] [medium] Linux Kernel: Multiple vulnerabilitiescert-bund
More from Ubuntu Security Notices
- unknownUSN-8659-4: Linux kernel (Oracle) vulnerability2026-08-26
- unknownUSN-8630-5: Linux kernel (Raspberry Pi) vulnerabilities2026-08-25
- unknownUSN-8658-3: Linux kernel vulnerabilities2026-08-25
- unknownUSN-8643-4: Linux kernel vulnerabilities2026-08-25
- unknownUSN-8659-3: Linux kernel (Azure) vulnerability2026-08-25