CVE-2026-63952 (GCVE-0-2026-63952)
Vulnerability from cvelistv5
Published
2026-07-19 14:55
Modified
2026-10-19 20:17
Severity ?
8.4 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N
Summary
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.
References
Impacted products
Vendor Product Version
Linux Linux Version: c4f75bc8bd6b3d62665e1f5400c419540edb5601
Version: c4f75bc8bd6b3d62665e1f5400c419540edb5601
Version: c4f75bc8bd6b3d62665e1f5400c419540edb5601
Version: c4f75bc8bd6b3d62665e1f5400c419540edb5601
Version: c4f75bc8bd6b3d62665e1f5400c419540edb5601
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