CVEvulnerability

CVE-2026-63952

8.4 HIGH Published 2026-07-19 Modified 2026-10-28 Official page ↗
Status
Analyzed
Published
2026-07-19
Last modified
2026-10-28
Assigner
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS 3.1 (416baaa9-dc9f-4396-8d5f-8c081fb06d67)
8.4 HIGH — CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N
Weaknesses
CWE-362

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.

Affected configurations

• linux linux kernel (>= 6.3 < 6.6.143) • linux linux kernel (>= 6.7 < 6.12.93) • linux linux kernel (>= 6.13 < 6.18.35) • linux linux kernel (>= 6.19 < 7.0.12) • linux linux kernel 7.1

Related

Weakness · CWE (1)

  • CWE-362 Concurrent Execution using Shared Resource with Improper Synchronization weakness

References