CVE-2023-53503
published 2025-10-01CVE-2023-53503: In the Linux kernel, the following vulnerability has been resolved: ext4: allow ext4_get_group_info() to fail Previously, ext4_get_group_info() would treat an…
PriorityP422medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.14%
4.2th percentile
In the Linux kernel, the following vulnerability has been resolved:
ext4: allow ext4_get_group_info() to fail
Previously, ext4_get_group_info() would treat an invalid group number
as BUG(), since in theory it should never happen. However, if a
malicious attaker (or fuzzer) modifies the superblock via the block
device while it is the file system is mounted, it is possible for
s_first_data_block to get set to a very large number. In that case,
when calculating the block group of some block number (such as the
starting block of a preallocation region), could result in an
underflow and very large block group number. Then the BUG_ON check in
ext4_get_group_info() would fire, resutling in a denial of service
attack that can be triggered by root or someone with write access to
the block device.
For a quality of implementation perspective, it's best that even if
the system administrator does something that they shouldn't, that it
will not trigger a BUG. So instead of BUG'ing, ext4_get_group_info()
will call ext4_error and return NULL. We also add fallback code in
all of the callers of ext4_get_group_info() that it might NULL.
Also, since ext4_get_group_info() was already borderline to be an
inline function, un-inline it. The results in a next reduction of the
compiled text size of ext4 by roughly 2k.
Affected
16 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.1.37-1 (bookworm) | linux 6.1.37-1 (bookworm) |
| linux | linux | — | — |
| linux | linux | >= 2f2e09eb15849562aede80ed007658e4504ded26 < 100c0ad6c04597fefeaaba2bb1827cc015d95067 | 100c0ad6c04597fefeaaba2bb1827cc015d95067 |
| linux | linux | >= 2f2e09eb15849562aede80ed007658e4504ded26 < 620a3c28221bb219b81bc0bffd065cc187494302 | 620a3c28221bb219b81bc0bffd065cc187494302 |
| linux | linux | >= 2f2e09eb15849562aede80ed007658e4504ded26 < b4319e457d6e3fb33e443efeaf4634fc36e8a9ed | b4319e457d6e3fb33e443efeaf4634fc36e8a9ed |
| linux | linux | >= 2f2e09eb15849562aede80ed007658e4504ded26 < 31668cebf45adfb6283e465e641c4f5a21b07afa | 31668cebf45adfb6283e465e641c4f5a21b07afa |
| linux | linux | >= 2f2e09eb15849562aede80ed007658e4504ded26 < 5354b2af34064a4579be8bc0e2f15a7b70f14b5f | 5354b2af34064a4579be8bc0e2f15a7b70f14b5f |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 5.10.191-1 | 5.10.191-1 |
| linux | linux_kernel | >= 0 < 6.1.37-1 | 6.1.37-1 |
| linux | linux_kernel | >= 0 < 6.3.7-1 | 6.3.7-1 |
| linux | linux_kernel | >= 0 < 6.3.7-1 | 6.3.7-1 |
| linux | linux_kernel | >= 3.11 < 5.10.181 | 5.10.181 |
| linux | linux_kernel | >= 5.11 < 5.15.113 | 5.15.113 |
| linux | linux_kernel | >= 5.16 < 6.1.30 | 6.1.30 |
| linux | linux_kernel | >= 6.2 < 6.3.4 | 6.3.4 |
CVSS provenance
nvdv3.15.5MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
osv5.5MEDIUM
vendor_debian5.5MEDIUM
vendor_redhat5.5MEDIUM
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Red Hat
kernel: ext4: allow ext4_get_group_info() to fail
vendor_redhat·2025-10-01·CVSS 5.5
CVE-2023-53503 [MEDIUM] CWE-787 kernel: ext4: allow ext4_get_group_info() to fail
kernel: ext4: allow ext4_get_group_info() to fail
In the Linux kernel, the following vulnerability has been resolved:
ext4: allow ext4_get_group_info() to fail
Previously, ext4_get_group_info() would treat an invalid group number
as BUG(), since in theory it should never happen. However, if a
malicious attaker (or fuzzer) modifies the superblock via the block
device while it is the file system is mounted, it is possible for
s_first_data_block to get set to a very large number. In that case,
when calculating the block group of some block number (such as the
starting block of a preallocation region), could result in an
underflow and very large block group number. Then the BUG_ON check in
ext4_get_group_info() would fire, resutling in a denial of service
attack that can be triggered by root
Debian
CVE-2023-53503: linux - In the Linux kernel, the following vulnerability has been resolved: ext4: allow...
vendor_debian·2023·CVSS 5.5
CVE-2023-53503 [MEDIUM] CVE-2023-53503: linux - In the Linux kernel, the following vulnerability has been resolved: ext4: allow...
In the Linux kernel, the following vulnerability has been resolved: ext4: allow ext4_get_group_info() to fail Previously, ext4_get_group_info() would treat an invalid group number as BUG(), since in theory it should never happen. However, if a malicious attaker (or fuzzer) modifies the superblock via the block device while it is the file system is mounted, it is possible for s_first_data_block to get set to a very large number. In that case, when calculating the block group of some block number (such as the starting block of a preallocation region), could result in an underflow and very large block group number. Then the BUG_ON check in ext4_get_group_info() would fire, resutling in a denial of service attack that can be triggered by root or someone with write access to the block device. F
GHSA
GHSA-794g-3p8m-5jpc: In the Linux kernel, the following vulnerability has been resolved:
ext4: allow ext4_get_group_info() to fail
Previously, ext4_get_group_info() woul
ghsa_unreviewed·2025-10-01
CVE-2023-53503 [MEDIUM] CWE-476 GHSA-794g-3p8m-5jpc: In the Linux kernel, the following vulnerability has been resolved:
ext4: allow ext4_get_group_info() to fail
Previously, ext4_get_group_info() woul
In the Linux kernel, the following vulnerability has been resolved:
ext4: allow ext4_get_group_info() to fail
Previously, ext4_get_group_info() would treat an invalid group number
as BUG(), since in theory it should never happen. However, if a
malicious attaker (or fuzzer) modifies the superblock via the block
device while it is the file system is mounted, it is possible for
s_first_data_block to get set to a very large number. In that case,
when calculating the block group of some block number (such as the
starting block of a preallocation region), could result in an
underflow and very large block group number. Then the BUG_ON check in
ext4_get_group_info() would fire, resutling in a denial of service
attack that can be triggered by root or someone with write access to
the block device.
OSV
CVE-2023-53503: In the Linux kernel, the following vulnerability has been resolved: ext4: allow ext4_get_group_info() to fail Previously, ext4_get_group_info() would
osv·2025-10-01·CVSS 5.5
CVE-2023-53503 [MEDIUM] CVE-2023-53503: In the Linux kernel, the following vulnerability has been resolved: ext4: allow ext4_get_group_info() to fail Previously, ext4_get_group_info() would
In the Linux kernel, the following vulnerability has been resolved: ext4: allow ext4_get_group_info() to fail Previously, ext4_get_group_info() would treat an invalid group number as BUG(), since in theory it should never happen. However, if a malicious attaker (or fuzzer) modifies the superblock via the block device while it is the file system is mounted, it is possible for s_first_data_block to get set to a very large number. In that case, when calculating the block group of some block number (such as the starting block of a preallocation region), could result in an underflow and very large block group number. Then the BUG_ON check in ext4_get_group_info() would fire, resutling in a denial of service attack that can be triggered by root or someone with write access to the block device. F
No detection rules found.
No public exploits indexed.
https://git.kernel.org/stable/c/100c0ad6c04597fefeaaba2bb1827cc015d95067https://git.kernel.org/stable/c/31668cebf45adfb6283e465e641c4f5a21b07afahttps://git.kernel.org/stable/c/5354b2af34064a4579be8bc0e2f15a7b70f14b5fhttps://git.kernel.org/stable/c/620a3c28221bb219b81bc0bffd065cc187494302https://git.kernel.org/stable/c/b4319e457d6e3fb33e443efeaf4634fc36e8a9ed
2025-10-01
Published