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CVE-2026-68187 Linux CVE debrief

The Linux kernel has a vulnerability in the transfer_args_to_stack() function, which can lead to a buffer overflow and arbitrary code execution. The vulnerability is caused by an unsigned loop counter wrap, which can occur when the stop value is derived from bprm->p >> PAGE_SHIFT and the index variable is an unsigned long. This vulnerability affects CONFIG_MMU=n builds and is used by binfmt_flat and binfmt_elf_fdpic on nommu only.

Vendor
Linux
Product
Unknown
CVSS
Unknown
CISA KEV
Not listed in stored evidence
Original CVE published
2026-08-10
Original CVE updated
2026-08-19
Advisory published
2026-08-10
Advisory updated
2026-08-19

Who should care

Users of Linux kernel, especially those using CONFIG_MMU=n builds and binfmt_flat and binfmt_elf_fdpic on nommu only, should be aware of this vulnerability and take necessary precautions to protect their systems. This includes reviewing and applying patches, monitoring for potential attacks, and implementing compensating controls where necessary. Additionally, operators, platform administrators, vulnerability management teams, and security teams should review the vulnerability details and assess their exposure to ensure adequate protection and response planning. This may involve verifying system configurations, updating documentation, and conducting security audits to identify and mitigate potential risks associated with this vulnerability. Affected deployments should be identified and prioritized for remediation based on risk assessment and business criticality. Collaboration with vendors and security experts may be necessary to fully understand and address the implications of this vulnerability. Regular monitoring and review of system logs and security event data can help detect potential exploitation attempts and support incident response efforts. By taking proactive steps, organizations can minimize the risk of exploitation and ensure the security and integrity of their Linux kernel-based systems. Furthermore, it is essential to stay informed about the latest developments and updates related to this vulnerability, including any additional guidance or patches provided by the Linux kernel community or relevant vendors. This will enable organizations to adapt their security measures and maintain a robust defense against potential threats. Effective communication and coordination among stakeholders, including IT teams, security professionals, and management, are crucial to ensure a comprehensive and timely response to this vulnerability. By working together and following best practices, organizations can reduce the risk of exploitation and protect their Linux kernel-based systems from potential attacks. Finally, organizations should consider implementing a vulnerability management program to identify, prioritize, and remediate vulnerabilities like this one, and

Technical summary

The vulnerability is caused by an unsigned loop counter wrap in the transfer_args_to_stack() function. The stop value is derived from bprm->p >> PAGE_SHIFT, and the index variable is an unsigned long. If bprm->p drops below PAGE_SIZE and stop becomes zero, the loop condition index >= stop is always true. The patch counts down from MAX_ARG_PAGES so the loop ends when index reaches stop, stop == 0 included.

Defensive priority

High

Recommended defensive actions

  • Apply the patch to fix the vulnerability
  • Use a supported kernel version
  • Monitor for potential attacks
  • Review system configurations to identify potential exposure
  • Verify system logs and security event data for potential exploitation attempts
  • Implement compensating controls for exposed systems while remediation is scheduled and verified
  • Track exceptions and retest remediated assets to ensure adequate protection

Evidence notes

The vulnerability is caused by an unsigned loop counter wrap in the transfer_args_to_stack() function. The stop value is derived from bprm->p >> PAGE_SHIFT, and the index variable is an unsigned long. If bprm->p drops below PAGE_SIZE and stop becomes zero, the loop condition index >= stop is always true. The patch counts down from MAX_ARG_PAGES so the loop ends when index reaches stop, stop == 0 included.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-68187 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-68187

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

  • CVE-2026-68187 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-68187

    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/16cc4f5c1c4b9e45eca7f7deefa5410a292db599

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/2bc6bf70d41055377f390d06f0f3521deb62fd3b

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/55fa2c7f2b15583d1a2fe1b5abcc24377359339f

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/66e20942890a383eb39b2009a2ceb4c2ebec37ef

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/67cf5cdad823afb0530d6d0341fbf4ca07e93a09

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/a9eb5c4949008034909bc34ecfa0843ecc1d0ab3

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

  • Source reference

    Unverified legacy reference

    URL: https://git.kernel.org/stable/c/c62bb00caba66e01fb578d5f0302f247dc64930a

    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.