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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-63952 Detail

Description

In the Linux kernel, the following vulnerability has been resolved: memfd: deny writeable mappings when implying SEAL_WRITE When SEAL_EXEC is added, SEAL_WRITE is implied to make W^X. But the implied seal is set after the check that makes sure the memfd can not have any writable mappings. This means one can use SEAL_EXEC to apply SEAL_WRITE while having writeable mappings. This breaks the contract that SEAL_WRITE provides and can be used by an attacker to pass a memfd that appears to be write sealed but can still be modified arbitrarily. Fix this by adding the implied seals before the call for mapping_deny_writable() is done.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://git.kernel.org/stable/c/0995d1f79aed8ccbf62056189dd53fd19726ea08 kernel.org
https://git.kernel.org/stable/c/3b041514cb6eae45869b020f743c14d983363222 kernel.org
https://git.kernel.org/stable/c/3be2a24f7f72ad7321ed6ad1715b956a4527bcf4 kernel.org
https://git.kernel.org/stable/c/555702282d4536a865dfffb1cd4f6028f196e7e8 kernel.org
https://git.kernel.org/stable/c/b3f4f82d1315f1439059a83d1c22c51a5b43d99e kernel.org

Weakness Enumeration

CWE-ID CWE Name Source

Change History

2 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-63952
NVD Published Date:
07/19/2026
NVD Last Modified:
07/20/2026
Source:
kernel.org