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CVE-2026-53099 Linux CVE debrief

A MEDIUM severity vulnerability was found in the Linux kernel, with a CVSS score of 5.5. The vulnerability was resolved by switching CONFIG_CFI_CLANG to CONFIG_CFI. This change was made due to a rename in commit 23ef9d439769, making the code compiler-agnostic. The vulnerability affects users of the Linux kernel, particularly those using version 7.0. The issue was caused by the incorrect use of CONFIG_CFI_CLANG, which was renamed to CONFIG_CFI. This incorrect usage resulted in the code being compiled out, leading to CFI failures for btf_dtor_kfunc_t.

Vendor
Linux
Product
Unknown
CVSS
MEDIUM 5.5
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-24
Original CVE updated
2026-07-21
Advisory published
2026-06-24
Advisory updated
2026-07-21

Who should care

Users of the Linux kernel, particularly those using version 7.0, should be aware of this vulnerability and take steps to mitigate it. This includes inventorying and verifying Linux kernel versions to identify potentially affected systems, applying patches from the Linux kernel maintainers, and monitoring systems for potential CFI failures.

Technical summary

The vulnerability was caused by the incorrect use of CONFIG_CFI_CLANG, which was renamed to CONFIG_CFI in commit 23ef9d439769. This incorrect usage resulted in the code being compiled out, leading to CFI failures for btf_dtor_kfunc_t. The issue was resolved by switching to the correct configuration option. Users of the Linux kernel should be aware of this vulnerability and take steps to mitigate it.

Defensive priority

Medium priority should be given to patching affected Linux kernel systems, as the vulnerability has a MEDIUM severity score.

Recommended defensive actions

  • Inventory and verify Linux kernel versions to identify potentially affected systems.
  • Apply patches from the Linux kernel maintainers to address the vulnerability.
  • Monitor systems for potential CFI failures.
  • Consider implementing compensating controls, such as additional monitoring or security measures.
  • 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.

Evidence notes

The CVE record was published on 2026-06-24T17:17:24.140Z and last modified on 2026-07-21T18:21:22.497Z. The NVD entry is currently Analyzed. This information is based on the provided source corpus. Further verification is recommended to ensure accuracy.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-53099 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-53099

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

  • CVE-2026-53099 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-53099

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

Supplemental references

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/9b0cf064ea0a6bac5e1a5fb43b004fd52fbe2b3b

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

  • Mitigation or vendor reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/f74fce43dbc059e059b5346a670f697c0e97b1d0

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

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.