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CVE-2026-72015 Linux CVE debrief

The CVE-2026-72015 vulnerability is a double-free issue in the Linux kernel's fs/resctrl component. A pseudo-locked group's RMID is freed when it is created and again during unmount, resulting in a double-free error. This issue affects Linux kernel users and administrators, especially those using pseudo-locked groups. They should verify and mitigate its impact on their systems. The original free adds the RMID to the rmid_free_lru linked list, and the second free attempts to add it again, causing an issue. To address this, Linux kernel users should verify if their systems are using a vulnerable version and apply patches or mitigations as available.

Vendor
Linux
Product
Unknown
CVSS
Unknown
CISA KEV
Not listed in stored evidence
Original CVE published
2026-08-15
Original CVE updated
2026-08-23
Advisory published
2026-08-15
Advisory updated
2026-08-23

Who should care

Linux kernel users and administrators, especially those using pseudo-locked groups, should be aware of this vulnerability and take steps to verify and mitigate its impact on their systems. They should review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance. Additionally, they should plan vendor-supported updates or mitigations through normal change control where exposure is confirmed and review compensating controls for exposed systems while remediation is scheduled and verified. System operators, platform administrators, vulnerability management teams, and security teams should also be aware of the potential impact on their systems and take necessary precautions. This includes checking relevant monitoring, detection, and logs for exposed assets that need extra review and tracking exceptions, retesting remediated assets, and closing the item only after evidence is documented. Linux kernel users should also consider implementing compensating controls for affected systems and monitoring system logs for potential exploitation attempts. Those responsible for asset inventory and patch management should prioritize patching or mitigating affected systems. Overall, a coordinated effort is required to address this vulnerability and minimize its impact. Those who should care include Linux kernel developers, system administrators, security teams, and IT professionals responsible for maintaining and securing Linux-based systems. They should work together to ensure that affected systems are identified and patched or mitigated in a timely manner. The vulnerability affects various Linux kernel versions and has been resolved in later versions. Users should verify their kernel versions and apply patches or upgrades as necessary. In addition to patching, users should also consider implementing additional security measures, such as monitoring system logs and implementing compensating controls, to minimize the risk of exploitation. By taking these steps, Linux kernel users and administrators can help prevent the exploitation of this vulnerability and protect their systems from potential attacks. The double-free issue can have a

Technical summary

The CVE-2026-72015 vulnerability is a double-free issue in the Linux kernel's fs/resctrl component. When a pseudo-locked group is created, its RMID is freed. During unmount, rmdir_all_sub() frees all RMIDs of all groups unconditionally, leading to a double-free of the pseudo-locked group's RMID. This results in the RMID being added to the rmid_free_lru linked list twice, causing an error. Linux kernel users should verify if their systems are using a vulnerable version and apply patches or mitigations as available. The vulnerability has a significant impact on system stability and security.

Defensive priority

Linux kernel users should verify if their systems are using a vulnerable version and apply patches or mitigations as available.

Recommended defensive actions

  • Verify Linux kernel versions and apply patches or mitigations as available
  • Monitor system logs for potential exploitation attempts
  • Consider implementing compensating controls for affected systems
  • 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
  • Check relevant monitoring, detection, and logs for exposed assets that need extra review
  • Track exceptions, retest remediated assets, and close the item only after evidence is documented

Evidence notes

The CVE-2026-72015 vulnerability involves a double-free issue in the Linux kernel's fs/resctrl component. A pseudo-locked group's RMID is freed when it is created and again during unmount, resulting in a double-free error. The original free adds the RMID to the rmid_free_lru linked list, and the second free attempts to add it again, causing an issue.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-72015 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-72015

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-72015 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-72015

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/52007bfdce5310e8c8a29849bfbfb188a1e50ca0

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/9168176894332312c12ef052e784735dbf4ffe3f

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/b2fe9e140aa94b2816aab7ebc692b543e418f5e3

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/b9f089723aee892efc77c349ae47a6b452b293c4

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/f7628eea9212e185a09df3aea603ca8580b8678d

    416baaa9-dc9f-4396-8d5f-8c081fb06d67

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.