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CVE-2026-53185 Linux CVE debrief

A use-after-free vulnerability was discovered in the Linux kernel's zram component. The issue arises from the zram_bvec_write_partial function, which passes its parent bio down, allowing the read to be dispatched asynchronously. This leads to the caller running memcpy_from_bvec, zram_write_page, and __free_page on the buffer, leaving the async read to write into a freed page. The vulnerability has been resolved through a series of commits, including 4e3c87b9421d. Users should update their Linux kernel to the latest version to mitigate this high-severity vulnerability.

Vendor
Linux
Product
Unknown
CVSS
HIGH 7.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-25
Original CVE updated
2026-06-28
Advisory published
2026-06-25
Advisory updated
2026-06-28

Who should care

System administrators and security teams responsible for Linux kernel-based systems should be aware of this vulnerability. Given its high CVSS score of 7.8, this vulnerability poses a significant risk to systems that have not been patched. Immediate attention is required to ensure the system's security and prevent potential attacks.

Technical summary

The vulnerability is caused by the zram_bvec_write_partial function passing its parent bio down, allowing the read to be dispatched asynchronously. This leads to a use-after-free scenario, where the caller runs memcpy_from_bvec, zram_write_page, and __free_page on the buffer, leaving the async read to write into a freed page. The issue has been addressed through a series of commits, including 4e3c87b9421d, which fixes the synchronous reads. However, the write_partial counterpart was missed, leading to this vulnerability. The CVSS vector for this vulnerability is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Defensive priority

High priority should be given to patching this vulnerability, as it has a high CVSS score and could lead to significant security risks if exploited. System administrators should ensure that their Linux kernel is updated to the latest version to mitigate this vulnerability.

Recommended defensive actions

  • Update the Linux kernel to the latest version to ensure the vulnerability is patched.
  • Review system logs for any suspicious activity related to the zram component.
  • Implement additional security measures, such as monitoring and intrusion detection systems, to detect potential attacks.
  • Conduct regular vulnerability assessments to identify and address potential security risks.
  • Ensure that all necessary security updates and patches are applied to the system.

Evidence notes

The vulnerability was discovered in the Linux kernel's zram component. The CVSS score for this vulnerability is 7.8, indicating a high severity. The vulnerability has been resolved through a series of commits, including 4e3c87b9421d. However, the write_partial counterpart was missed, leading to this vulnerability. The source of this information is the NVD database, which provides detailed information on vulnerabilities, including their CVSS scores and potential impacts.

Official resources

This article is AI-assisted and based on the supplied source corpus.