CVE-2026-63952

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description An issue exists in the memfd component where the SEAL WRITE seal is implied when SEAL EXEC is added to enforce W^X (Write XOR Execute), a security policy ensuring memory is either writable or executable, but not both. The implied seal is applied after the check that verifies the memfd has no writable mappings. This allows a user to apply SEAL WRITE while maintaining writable mappings, enabling an attacker to provide a memfd that appears write-sealed but remains arbitrarily modifiable.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.