cbcvebase.
CVE-2024-50182
published 2024-11-08

CVE-2024-50182: In the Linux kernel, the following vulnerability has been resolved: secretmem: disable memfd_secret() if arch cannot set direct map Return -ENOSYS from…

PriorityP420medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.23%
14.1th percentile
In the Linux kernel, the following vulnerability has been resolved: secretmem: disable memfd_secret() if arch cannot set direct map Return -ENOSYS from memfd_secret() syscall if !can_set_direct_map(). This is the case for example on some arm64 configurations, where marking 4k PTEs in the direct map not present can only be done if the direct map is set up at 4k granularity in the first place (as ARM's break-before-make semantics do not easily allow breaking apart large/gigantic pages). More precisely, on arm64 systems with !can_set_direct_map(), set_direct_map_invalid_noflush() is a no-op, however it returns success (0) instead of an error. This means that memfd_secret will seemingly "work" (e.g. syscall succeeds, you can mmap the fd and fault in pages), but it does not actually achieve its goal of removing its memory from the direct map. Note that with this patch, memfd_secret() will start erroring on systems where can_set_direct_map() returns false (arm64 with CONFIG_RODATA_FULL_DEFAULT_ENABLED=n, CONFIG_DEBUG_PAGEALLOC=n and CONFIG_KFENCE=n), but that still seems better than the current silent failure. Since CONFIG_RODATA_FULL_DEFAULT_ENABLED defaults to 'y', most arm64 systems actually have a working memfd_secret() and aren't be affected. From going through the iterations of the original memfd_secret patch series, it seems that disabling the syscall in these scenarios was the intended behavior [1] (preferred over having set_direct_map_invalid_noflush return an error as that would result in SIGBUSes at page-fault time), however the check for it got dropped between v16 [2] and v17 [3], when secretmem moved away from CMA allocations. [1]: https://lore.kernel.org/lkml/[email protected]/ [2]: https://lore.kernel.org/lkml/[email protected]/#t [3]: https://lore.kernel.org/lkml/[email protected]/

Affected

24 ranges
VendorProductVersion rangeFixed in
debianlinux< linux 6.1.115-1 (bookworm)linux 6.1.115-1 (bookworm)
debianlinux-6.1< linux 6.1.115-1 (bookworm)linux 6.1.115-1 (bookworm)
linuxlinux
linuxlinux>= 1507f51255c9ff07d75909a84e7c0d7f3c4b2f49 < d0ae6ffa1aeb297aef89f49cfb894a83c329ebadd0ae6ffa1aeb297aef89f49cfb894a83c329ebad
linuxlinux>= 1507f51255c9ff07d75909a84e7c0d7f3c4b2f49 < 5ea0b7af38754d2b45ead9257bca47e84662e9265ea0b7af38754d2b45ead9257bca47e84662e926
linuxlinux>= 1507f51255c9ff07d75909a84e7c0d7f3c4b2f49 < 7caf966390e6e4ebf42775df54e7ee1f280ce6777caf966390e6e4ebf42775df54e7ee1f280ce677
linuxlinux>= 1507f51255c9ff07d75909a84e7c0d7f3c4b2f49 < 757786abe4547eb3d9d0e8350a63bdb0f9824af2757786abe4547eb3d9d0e8350a63bdb0f9824af2
linuxlinux>= 1507f51255c9ff07d75909a84e7c0d7f3c4b2f49 < 532b53cebe58f34ce1c0f34d866f5c0e335c53c6532b53cebe58f34ce1c0f34d866f5c0e335c53c6
linuxlinux_kernel
linuxlinux_kernel
linuxlinux_kernel>= 0 < 6.1.115-16.1.115-1
linuxlinux_kernel>= 0 < 6.11.4-16.11.4-1
linuxlinux_kernel>= 0 < 6.11.4-16.11.4-1
linuxlinux_kernel>= 0 < 5.15.0-133.1445.15.0-133.144
linuxlinux_kernel>= 0 < 6.8.0-56.586.8.0-56.58
linuxlinux_kernel>= 0 < 6.11.0-18.186.11.0-18.18
linuxlinux_kernel>= 5.14 < 5.15.1695.15.169
linuxlinux_kernel>= 5.16 < 6.1.1136.1.113
linuxlinux_kernel>= 6.2 < 6.6.576.6.57
linuxlinux_kernel>= 6.7 < 6.11.46.11.4
msrccbl2_kernel_5.15.167.1-2_on_cbl_mariner_2.0
msrccbl2_kernel_5.15.173.1-1_on_cbl_mariner_2.0
msrccbl_mariner_2.0_arm
msrccbl_mariner_2.0_x64

CVSS provenance

nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv8.8HIGH
vendor_ubuntu8.8HIGH
vendor_debian5.5MEDIUM
vendor_msrc5.5MEDIUM
vendor_redhat5.5MEDIUM
Stop checking back — get the weekly exploitation signal.

Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.