Multiple vulnerabilities in Debian Linux kernel (July 24, 2026)

unknownCVE-2026-53027 CVE-2026-63818 CVE-2026-53399 CVE-2025-21807 CVE-2026-64189 CVE-2026-63815

Multiple vulnerabilities have been discovered in the Debian Linux kernel. They allow an attacker to cause privilege escalation, a breach of data confidentiality, and a breach of data integrity.

CSIRTS triage

vendor: Debian product: Linux kernel Privilege escalation Information disclosure

What: Multiple vulnerabilities allow an attacker to cause privilege escalation and breach data confidentiality and integrity.
Who is affected: Deployments of the Debian Linux kernel are affected.
Urgency: Remediation is urgent due to the potential for privilege escalation and data breaches, though exploitation status is currently unknown.
Action: Users should update their Debian Linux kernel to the latest version.

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

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Details

Source: CERT-FR Avis de sécurité (FR · national-cert · site)
Severity: unknown
Published: 2026-07-24
Exploitation: Not in CISA KEV at last sync
Language: Machine-translated to English — verify against the original

Original advisory: https://www.cert.ssi.gouv.fr/avis/CERTFR-2026-AVI-0930/

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.

Low exploitation riskCVE-2026-530270.12% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 2% of all scored CVEs.
Low exploitation riskCVE-2026-638180.13% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 3% of all scored CVEs.
Low exploitation riskCVE-2026-533990.51% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 41% of all scored CVEs.
Low exploitation riskCVE-2025-218070.14% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 4% of all scored CVEs.
Low exploitation riskCVE-2026-641890.12% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 2% of all scored CVEs.
Low exploitation riskCVE-2026-638150.13% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 3% of all scored CVEs.
Low exploitation riskCVE-2026-638160.12% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 2% of all scored CVEs.
Low exploitation riskCVE-2026-534020.13% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 3% of all scored CVEs.
Low exploitation riskCVE-2026-533920.50% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 40% of all scored CVEs.
Low exploitation riskCVE-2026-641870.16% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 6% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-53027	coverage & exploitation status	NVD · CVE.org
CVE-2026-63818	coverage & exploitation status	NVD · CVE.org
CVE-2026-53399	coverage & exploitation status	NVD · CVE.org
CVE-2025-21807	coverage & exploitation status	NVD · CVE.org
CVE-2026-64189	coverage & exploitation status	NVD · CVE.org
CVE-2026-63815	coverage & exploitation status	NVD · CVE.org
CVE-2026-63816	coverage & exploitation status	NVD · CVE.org
CVE-2026-53402	coverage & exploitation status	NVD · CVE.org
CVE-2026-53392	coverage & exploitation status	NVD · CVE.org
CVE-2026-64187	coverage & exploitation status	NVD · CVE.org
CVE-2026-53226	coverage & exploitation status	NVD · CVE.org
CVE-2026-46093	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

medium[NEW] [medium] Linux Kernel: Multiple vulnerabilities allow unspecified attackcert-bund
highUSN-8618-1: Linux kernel vulnerabilitiesubuntu
medium[NEW] [medium] Linux Kernel: Multiple vulnerabilitiescert-bund
highUSN-8603-1: Linux kernel (Azure) vulnerabilitiesubuntu
highUSN-8593-1: Linux kernel vulnerabilitiesubuntu
unknownDSA-6393-1 linux - security updatedebian
highCVE-2026-64189: In the Linux kernel, the following vulnerability has been resolved: netfilter: ipset: fix race…nvd
unknownCVE-2026-64187: In the Linux kernel, the following vulnerability has been resolved: xfs: fail recovery on a co…nvd
highUSN-8569-1: Linux kernel (HWE) vulnerabilitiesubuntu
highUSN-8568-1: Linux kernel (OEM) vulnerabilitiesubuntu
highUSN-8566-1: Linux kernel vulnerabilitiesubuntu
highCVE-2026-63818: In the Linux kernel, the following vulnerability has been resolved: f2fs: validate orphan inod…nvd

Recent advisories for Debian Linux kernel

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

unknownMultiple vulnerabilities in Debian LTS Linux kernel (July 24, 2026)cert-fr-avis · 2026-07-24
unknownMultiple vulnerabilities in Debian LTS Linux kernel (July 10, 2026)cert-fr-avis · 2026-07-10
unknownDebian Linux Kernel Multiple Vulnerabilitieshkcert · 2026-07-06
unknownDebian Linux Kernel Multiple Vulnerabilitieshkcert · 2026-06-30
unknownMultiple vulnerabilities in the Debian Linux kernel (June 26, 2026)cert-fr-avis · 2026-06-26