CVE-2026-63952

CVE CVE-2026-63952EUVD EUVD-2026-45725Published 2026-07-19T14:55:44.000ZLast changed 2026-08-05T12:37:37.000ZCVSS 8.4

What the advisory describes

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.

Source: EUVD (ENISA), in the words of the advisory.

Products the advisory names

These come from the advisory itself, not from any check we performed.

Linux — Linux patch: 7.1; patch: 0; patch: 6.18.35; patch: 6.12.93; c4f75bc8bd6b3d62665e1f5400c419540edb5601 <b3f4f82d1315f1439059a83d1c22c51a5b43d99e; c4f75bc8bd6b3d62665e1f5400c419540edb5601 <0995d1f79aed8ccbf62056189dd53fd19726ea08; patch: 6.6.143; patch: 7.0.12; c4f75bc8bd6b3d62665e1f5400c419540edb5601 <3b041514cb6eae45869b020f743c14d983363222; c4f75bc8bd6b3d62665e1f5400c419540edb5601 <3be2a24f7f72ad7321ed6ad1715b956a4527bcf4; 6.3; c4f75bc8bd6b3d62665e1f5400c419540edb5601 <555702282d4536a865dfffb1cd4f6028f196e7e8

The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.

Carried in the product catalogue

An estate covering these products can be recorded in Patchlage. An advisory about them appears in the next morning's situation report.

Linux — Linux

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