USN-8633-1: Linux kernel vulnerabilities

unknownpublic exploitCVE-2020-24588 CVE-2025-27558 CVE-2021-47354 CVE-2021-47378 CVE-2024-38612 CVE-2026-31405

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; - GPU drivers; - InfiniBand drivers; - Media drivers; - NVIDIA Tegra memory controller driver; - Network drivers; - STMicroelectronics network drivers; - NVME drivers; - 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; (CVE-2021-47354, CVE-2021-47378, CVE-2024-38612, CVE-2026-31405, CVE-2026-31414, CVE-2026-31448, CVE-2026-31649, CVE-2026-31657, CVE-2026-31668, CVE-2026-43198, CVE-2026-43493, CVE-2026-43499, CVE-2026-46266, CVE-2026-46331, CVE-2026-52924, CVE-2026-52931, CVE-2026-52955, CVE-2026-52982, CVE-2026-52986, CVE-2026-53002, CVE-2026-53006, CVE-2026-53045, CVE-2026-53088, CVE-2026-53176, CVE-2026-53225, CVE-2026-53228, CVE-2026-53359)

CSIRTS triage

vendor: Linux product: Linux kernel Remote code execution Privilege escalation Information disclosure Denial of service Memory corruption

What: WiFi mesh frame injection (CVE-2025-27558) and multiple flaws in x86, GPU, network, and protocol subsystems.
Who is affected: Systems with WiFi mesh capabilities and systems running affected Linux kernel versions across multiple subsystems.
Urgency: High; WiFi injection vulnerability affects physical proximity attackers and container environments; prioritize patching.
Action: Apply kernel security update USN-8633-1 from Ubuntu security repositories immediately.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Ubuntu Security Notices (INTL · vendor-psirt · site)
Severity: unknown
Published: 2026-08-12
Exploitation: Not in CISA KEV at last sync

Original advisory: https://ubuntu.com/security/notices/USN-8633-1

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.
Low exploitation riskCVE-2021-473540.73% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 51% 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-2024-386120.68% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 49% 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 43% 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-2026-316490.46% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 38% 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.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2020-24588	coverage & exploitation status	NVD · CVE.org
CVE-2025-27558	coverage & exploitation status	NVD · CVE.org
CVE-2021-47354	coverage & exploitation status	NVD · CVE.org
CVE-2021-47378	coverage & exploitation status	NVD · CVE.org
CVE-2024-38612	coverage & exploitation status	NVD · CVE.org
CVE-2026-31405	coverage & exploitation status	NVD · CVE.org
CVE-2026-31414	coverage & exploitation status	NVD · CVE.org
CVE-2026-31448	coverage & exploitation status	NVD · CVE.org
CVE-2026-31649	coverage & exploitation status	NVD · CVE.org
CVE-2026-31657	coverage & exploitation status	NVD · CVE.org
CVE-2026-31668	coverage & exploitation status	NVD · CVE.org
CVE-2026-43198	coverage & exploitation status	NVD · CVE.org
CVE-2026-43493	coverage & exploitation status	NVD · CVE.org
CVE-2026-43499	coverage & exploitation status	NVD · CVE.org
CVE-2026-46266	coverage & exploitation status	NVD · CVE.org
CVE-2026-46331	coverage & exploitation status	NVD · CVE.org
CVE-2026-52924	coverage & exploitation status	NVD · CVE.org
CVE-2026-52931	coverage & exploitation status	NVD · CVE.org
CVE-2026-52955	coverage & exploitation status	NVD · CVE.org
CVE-2026-52982	coverage & exploitation status	NVD · CVE.org
CVE-2026-52986	coverage & exploitation status	NVD · CVE.org
CVE-2026-53002	coverage & exploitation status	NVD · CVE.org
CVE-2026-53006	coverage & exploitation status	NVD · CVE.org
CVE-2026-53045	coverage & exploitation status	NVD · CVE.org
CVE-2026-53088	coverage & exploitation status	NVD · CVE.org
CVE-2026-53176	coverage & exploitation status	NVD · CVE.org
CVE-2026-53225	coverage & exploitation status	NVD · CVE.org
CVE-2026-53228	coverage & exploitation status	NVD · CVE.org
CVE-2026-53359	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

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