PatchSiren cyber security CVE debrief
CVE-2026-23433 Linux CVE debrief
CVE-2026-23433 is a MEDIUM severity vulnerability in the Linux kernel, specifically in the arm_mpam component. The vulnerability occurs when an MSC supporting memory bandwidth monitoring is brought offline and then online, causing a null pointer dereference when restoring bandwidth counters. This issue can lead to a kernel oops with a call trace. The vulnerability is resolved by providing a local variable for val to avoid the null pointer dereference. System administrators and security teams should be aware of this vulnerability and take necessary actions to mitigate the risk.
- Vendor
- Linux
- Product
- Unknown
- CVSS
- MEDIUM 5.5
- CISA KEV
- Not listed in stored evidence
- Original CVE published
- 2026-04-03
- Original CVE updated
- 2026-07-24
- Advisory published
- 2026-04-03
- Advisory updated
- 2026-07-24
Who should care
System administrators and security teams responsible for Linux kernel-based systems, especially those using arm_mpam, should be aware of this vulnerability and take necessary actions to mitigate the risk. This includes reviewing system configurations, monitoring system logs, and applying patches or updates provided by the Linux kernel maintainers.
Technical summary
The vulnerability is caused by the __ris_msmon_read() function being called without initializing the mbwu_arg.val variable, leading to a null pointer dereference when adding to it. The issue is resolved by providing a local variable for val to avoid the null pointer dereference. This vulnerability affects Linux kernel-based systems, specifically those using arm_mpam. The vulnerability has a MEDIUM severity and can cause a kernel oops.
Defensive priority
Apply patches or updates provided by the Linux kernel maintainers to fix the vulnerability. Review system configurations and ensure that arm_mpam is properly configured.
Recommended defensive actions
- Apply patches or updates provided by the Linux kernel maintainers to fix the vulnerability.
- Review system configurations and ensure that arm_mpam is properly configured.
- Monitor system logs for potential exploitation attempts.
- Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
- Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.
- Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.
Evidence notes
The CVE record was published on 2026-04-03T16:16:24.777Z and was last modified on 2026-07-24T21:10:00.143Z. The NVD entry is currently Analyzed. The vulnerability affects Linux kernel-based systems, specifically those using arm_mpam. Evidence is limited to public CVE and NVD information.
Official resources
-
CVE-2026-23433 CVE record
CVE.org
-
CVE-2026-23433 NVD detail
NVD
-
Source item URL
nvd_modified
-
Mitigation or vendor reference
416baaa9-dc9f-4396-8d5f-8c081fb06d67 - Patch
-
Mitigation or vendor reference
416baaa9-dc9f-4396-8d5f-8c081fb06d67 - Patch
AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-04-03T16:16:24.777Z and has not been modified since then. The NVD entry is currently Analyzed.