Red Hat Security Advisory: kernel security update
The kernel packages contain the Linux kernel, the core of any Linux operating system. Security Fix(es): * kernel: io_uring: prevent opcode speculation (CVE-2025-21863) * kernel: Linux kernel: vsock vulnerability may lead to memory corruption (CVE-2025-40248) * kernel: net: atlantic: fix fragment overflow handling in RX path (CVE-2025-68301) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
AI Analysis
Technical Summary
The advisory covers three kernel vulnerabilities affecting Red Hat Enterprise Linux 9.6 Extended Update Support. CVE-2025-21863 involves preventing opcode speculation in io_uring, CVE-2025-40248 addresses a vsock vulnerability that could lead to memory corruption, and CVE-2025-68301 fixes fragment overflow handling in the network atlantic RX path. Red Hat has released updated kernel packages containing fixes for these issues. The update must be applied and the system rebooted for the remediation to take effect. No CVSS scores are provided in the advisory, but the impact is rated as important by Red Hat Product Security.
Potential Impact
The vulnerabilities could allow an attacker to exploit opcode speculation in io_uring, cause memory corruption via the vsock interface, or trigger fragment overflow in the network RX path, potentially leading to system instability or compromise. The advisory rates these issues as having an important security impact, indicating significant risk if unpatched. No known exploits in the wild are reported at this time.
Mitigation Recommendations
Red Hat has released updated kernel packages for Red Hat Enterprise Linux 9.6 Extended Update Support that address these vulnerabilities. Users should apply the kernel update as detailed in the Red Hat advisory (https://access.redhat.com/articles/11258) and reboot affected systems to ensure the fixes take effect. This is the official and recommended remediation.
Red Hat Security Advisory: kernel security update
Description
The kernel packages contain the Linux kernel, the core of any Linux operating system. Security Fix(es): * kernel: io_uring: prevent opcode speculation (CVE-2025-21863) * kernel: Linux kernel: vsock vulnerability may lead to memory corruption (CVE-2025-40248) * kernel: net: atlantic: fix fragment overflow handling in RX path (CVE-2025-68301) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The advisory covers three kernel vulnerabilities affecting Red Hat Enterprise Linux 9.6 Extended Update Support. CVE-2025-21863 involves preventing opcode speculation in io_uring, CVE-2025-40248 addresses a vsock vulnerability that could lead to memory corruption, and CVE-2025-68301 fixes fragment overflow handling in the network atlantic RX path. Red Hat has released updated kernel packages containing fixes for these issues. The update must be applied and the system rebooted for the remediation to take effect. No CVSS scores are provided in the advisory, but the impact is rated as important by Red Hat Product Security.
Potential Impact
The vulnerabilities could allow an attacker to exploit opcode speculation in io_uring, cause memory corruption via the vsock interface, or trigger fragment overflow in the network RX path, potentially leading to system instability or compromise. The advisory rates these issues as having an important security impact, indicating significant risk if unpatched. No known exploits in the wild are reported at this time.
Mitigation Recommendations
Red Hat has released updated kernel packages for Red Hat Enterprise Linux 9.6 Extended Update Support that address these vulnerabilities. Users should apply the kernel update as detailed in the Red Hat advisory (https://access.redhat.com/articles/11258) and reboot affected systems to ensure the fixes take effect. This is the official and recommended remediation.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:1703
- Cve Count
- 3
- Additional Cves
- ["CVE-2025-40248","CVE-2025-68301"]
Threat ID: 6a3da1c74853345fc18209d5
Added to database: 06/25/2026, 21:46:47 UTC
Last enriched: 06/25/2026, 21:58:50 UTC
Last updated: 09/10/2026, 19:36:49 UTC
Views: 78
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