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: dm-flakey: Fix memory corruption in optional corrupt_bio_byte feature (CVE-2025-21966) * kernel: iscsi_ibft: Fix UBSAN shift-out-of-bounds warning in ibft_attr_show_nic() (CVE-2025-21993) 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
Red Hat Product Security issued an advisory (RHSA-2025:7956) for Red Hat Enterprise Linux 10 kernel packages to fix two vulnerabilities: CVE-2025-21966, a memory corruption flaw in the dm-flakey kernel module's optional corrupt_bio_byte feature, and CVE-2025-21993, a UBSAN shift-out-of-bounds warning in the iscsi_ibft kernel component. These issues are addressed by updated kernel packages that must be installed and followed by a system reboot. The advisory classifies the security impact as moderate. No CVSS scores are provided in the advisory, but the vulnerabilities relate to memory safety errors (CWE-119 and CWE-125).
Potential Impact
The vulnerabilities could lead to memory corruption or undefined behavior within the kernel, potentially affecting system stability or security. The advisory does not report known exploits in the wild. The impact is rated moderate by Red Hat, indicating a security risk that warrants timely patching but is not classified as critical.
Mitigation Recommendations
Red Hat has released updated kernel packages that fix these vulnerabilities. Users should apply the security update for Red Hat Enterprise Linux 10 as described in the Red Hat advisory RHSA-2025:7956 and reboot the system to activate the fixes. Patch status is confirmed as available and official. No additional mitigation steps are indicated by the vendor.
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: dm-flakey: Fix memory corruption in optional corrupt_bio_byte feature (CVE-2025-21966) * kernel: iscsi_ibft: Fix UBSAN shift-out-of-bounds warning in ibft_attr_show_nic() (CVE-2025-21993) 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
Red Hat Product Security issued an advisory (RHSA-2025:7956) for Red Hat Enterprise Linux 10 kernel packages to fix two vulnerabilities: CVE-2025-21966, a memory corruption flaw in the dm-flakey kernel module's optional corrupt_bio_byte feature, and CVE-2025-21993, a UBSAN shift-out-of-bounds warning in the iscsi_ibft kernel component. These issues are addressed by updated kernel packages that must be installed and followed by a system reboot. The advisory classifies the security impact as moderate. No CVSS scores are provided in the advisory, but the vulnerabilities relate to memory safety errors (CWE-119 and CWE-125).
Potential Impact
The vulnerabilities could lead to memory corruption or undefined behavior within the kernel, potentially affecting system stability or security. The advisory does not report known exploits in the wild. The impact is rated moderate by Red Hat, indicating a security risk that warrants timely patching but is not classified as critical.
Mitigation Recommendations
Red Hat has released updated kernel packages that fix these vulnerabilities. Users should apply the security update for Red Hat Enterprise Linux 10 as described in the Red Hat advisory RHSA-2025:7956 and reboot the system to activate the fixes. Patch status is confirmed as available and official. No additional mitigation steps are indicated by the vendor.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2025:7956
- Cve Count
- 2
- Additional Cves
- ["CVE-2025-21993"]
Threat ID: 6a3da1d14853345fc18250f4
Added to database: 06/25/2026, 21:46:57 UTC
Last enriched: 06/25/2026, 22:09:59 UTC
Last updated: 09/10/2026, 19:36:49 UTC
Views: 24
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