Red Hat Security Advisory: kernel-rt security update
A security vulnerability (CVE-2025-21785) affecting the Real Time Linux Kernel (kernel-rt) in Red Hat Enterprise Linux 8 has been addressed. The issue involves an out-of-bounds write to the cacheinfo array on arm64 architectures. Red Hat has released an important security update for kernel-rt packages to fix this vulnerability. Systems must be rebooted after applying the update for the fix to take effect.
AI Analysis
Technical Summary
The kernel-rt packages for Red Hat Enterprise Linux 8, which provide a Real Time Linux Kernel for high determinism systems, contain a vulnerability identified as CVE-2025-21785. This vulnerability is an out-of-bounds write to the cacheinfo array on arm64 architectures, classified under CWE-787. Red Hat Product Security has issued an important security advisory (RHSA-2025:3264) and released updated kernel-rt packages to address this issue. The update requires a system reboot to be effective.
Potential Impact
The vulnerability allows an out-of-bounds write in the kernel on arm64 systems, which could potentially lead to system instability or other unintended behavior. The security impact is rated as Important by Red Hat. No known exploits in the wild have been reported at this time.
Mitigation Recommendations
Red Hat has released updated kernel-rt packages that fix this vulnerability. Users should apply the security update as described in the Red Hat advisory RHSA-2025:3264 and reboot their systems to ensure the fix takes effect. Patch status is confirmed as an official fix provided by Red Hat.
Red Hat Security Advisory: kernel-rt security update
Description
A security vulnerability (CVE-2025-21785) affecting the Real Time Linux Kernel (kernel-rt) in Red Hat Enterprise Linux 8 has been addressed. The issue involves an out-of-bounds write to the cacheinfo array on arm64 architectures. Red Hat has released an important security update for kernel-rt packages to fix this vulnerability. Systems must be rebooted after applying the update for the fix to take effect.
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The kernel-rt packages for Red Hat Enterprise Linux 8, which provide a Real Time Linux Kernel for high determinism systems, contain a vulnerability identified as CVE-2025-21785. This vulnerability is an out-of-bounds write to the cacheinfo array on arm64 architectures, classified under CWE-787. Red Hat Product Security has issued an important security advisory (RHSA-2025:3264) and released updated kernel-rt packages to address this issue. The update requires a system reboot to be effective.
Potential Impact
The vulnerability allows an out-of-bounds write in the kernel on arm64 systems, which could potentially lead to system instability or other unintended behavior. The security impact is rated as Important by Red Hat. No known exploits in the wild have been reported at this time.
Mitigation Recommendations
Red Hat has released updated kernel-rt packages that fix this vulnerability. Users should apply the security update as described in the Red Hat advisory RHSA-2025:3264 and reboot their systems to ensure the fix takes effect. Patch status is confirmed as an official fix provided by Red Hat.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2025:3264
- Cve Count
- 1
- Additional Cves
- []
- Cvss Version
- null
Threat ID: 6a3da1d64853345fc1827287
Added to database: 06/25/2026, 21:47:02 UTC
Last enriched: 06/25/2026, 22:15:44 UTC
Last updated: 07/06/2026, 08:51:15 UTC
Views: 3
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