CVE-2026-23189
published 2026-02-14CVE-2026-23189: In the Linux kernel, the following vulnerability has been resolved: ceph: fix NULL pointer dereference in ceph_mds_auth_match() The CephFS kernel client has…
PriorityP422medium5.5CVSS 3.1
AVLACLPRLUINSUCNINAH
EPSS
0.11%
1.6th percentile
In the Linux kernel, the following vulnerability has been resolved:
ceph: fix NULL pointer dereference in ceph_mds_auth_match()
The CephFS kernel client has regression starting from 6.18-rc1.
We have issue in ceph_mds_auth_match() if fs_name == NULL:
const char fs_name = mdsc->fsc->mount_options->mds_namespace;
...
if (auth->match.fs_name && strcmp(auth->match.fs_name, fs_name)) {
/ fsname mismatch, try next one */
return 0;
}
Patrick Donnelly suggested that: In summary, we should definitely start
decoding `fs_name` from the MDSMap and do strict authorizations checks
against it. Note that the `-o mds_namespace=foo` should only be used for
selecting the file system to mount and nothing else. It's possible
no mds_namespace is specified but the kernel will mount the only
file system that exists which may have name "foo".
This patch reworks ceph_mdsmap_decode() and namespace_equals() with
the goal of supporting the suggested concept. Now struct ceph_mdsmap
contains m_fs_name field that receives copy of extracted FS name
by ceph_extract_encoded_string(). For the case of "old" CephFS file
systems, it is used "cephfs" name.
[ idryomov: replace redundant %*pE with %s in ceph_mdsmap_decode(),
get rid of a series of strlen() calls in ceph_namespace_match(),
drop changes to namespace_equals() body to avoid treating empty
mds_namespace as equal, drop changes to ceph_mdsc_handle_fsmap()
as namespace_equals() isn't an equivalent substitution there ]
Affected
13 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | linux | < linux 6.18.10-1 (forky) | linux 6.18.10-1 (forky) |
| linux | linux | — | — |
| linux | linux | — | — |
| linux | linux | >= 07640d34a781bb2e39020a39137073c03c4aa932 < c6f8326f26bd20d648d9a55afd68148d1b6afe28 | c6f8326f26bd20d648d9a55afd68148d1b6afe28 |
| linux | linux | >= 22c73d52a6d05c5a2053385c0d6cd9984732799d < 57b36ffc8881dd455d875f85c105901974af2130 | 57b36ffc8881dd455d875f85c105901974af2130 |
| linux | linux | >= 22c73d52a6d05c5a2053385c0d6cd9984732799d < 7987cce375ac8ce98e170a77aa2399f2cf6eb99f | 7987cce375ac8ce98e170a77aa2399f2cf6eb99f |
| linux | linux | >= 6.12.58 < 6.12.70 | 6.12.70 |
| linux | linux | >= 6.17.8 < 6.18 | 6.18 |
| linux | linux_kernel | — | — |
| linux | linux_kernel | >= 0 < 6.12.73-1 | 6.12.73-1 |
| linux | linux_kernel | >= 0 < 6.18.10-1 | 6.18.10-1 |
| linux | linux_kernel | >= 6.12.58 < 6.12.70 | 6.12.70 |
| linux | linux_kernel | >= 6.17.8 < 6.18.10 | 6.18.10 |
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_debian5.5LOW
vendor_redhat5.5MEDIUM
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Red Hat
kernel: ceph: fix NULL pointer dereference in ceph_mds_auth_match()
vendor_redhat·2026-02-14·CVSS 5.5
CVE-2026-23189 [MEDIUM] kernel: ceph: fix NULL pointer dereference in ceph_mds_auth_match()
kernel: ceph: fix NULL pointer dereference in ceph_mds_auth_match()
In the Linux kernel, the following vulnerability has been resolved:
ceph: fix NULL pointer dereference in ceph_mds_auth_match()
The CephFS kernel client has regression starting from 6.18-rc1.
We have issue in ceph_mds_auth_match() if fs_name == NULL:
const char fs_name = mdsc->fsc->mount_options->mds_namespace;
...
if (auth->match.fs_name && strcmp(auth->match.fs_name, fs_name)) {
/ fsname mismatch, try next one */
return 0;
}
Patrick Donnelly suggested that: In summary, we should definitely start
decoding `fs_name` from the MDSMap and do strict authorizations checks
against it. Note that the `-o mds_namespace=foo` should only be used for
selecting the file system to mount and nothing else. It's possible
no mds_namespace
Debian
CVE-2026-23189: linux - In the Linux kernel, the following vulnerability has been resolved: ceph: fix N...
vendor_debian·2026·CVSS 5.5
CVE-2026-23189 [MEDIUM] CVE-2026-23189: linux - In the Linux kernel, the following vulnerability has been resolved: ceph: fix N...
In the Linux kernel, the following vulnerability has been resolved: ceph: fix NULL pointer dereference in ceph_mds_auth_match() The CephFS kernel client has regression starting from 6.18-rc1. We have issue in ceph_mds_auth_match() if fs_name == NULL: const char fs_name = mdsc->fsc->mount_options->mds_namespace; ... if (auth->match.fs_name && strcmp(auth->match.fs_name, fs_name)) { / fsname mismatch, try next one */ return 0; } Patrick Donnelly suggested that: In summary, we should definitely start decoding `fs_name` from the MDSMap and do strict authorizations checks against it. Note that the `-o mds_namespace=foo` should only be used for selecting the file system to mount and nothing else. It's possible no mds_namespace is specified but the kernel will mount the only file system that exis
VulDB
Linux Kernel up to 6.12.69/6.18.9 FS File Parser ceph_mds_auth_match null pointer dereference (Nessus ID 299111 / WID-SEC-2026-0421)
vuldb·2026-05-05·CVSS 5.5
CVE-2026-23189 [MEDIUM] Linux Kernel up to 6.12.69/6.18.9 FS File Parser ceph_mds_auth_match null pointer dereference (Nessus ID 299111 / WID-SEC-2026-0421)
A vulnerability, which was classified as critical, has been found in Linux Kernel up to 6.12.69/6.18.9. Affected is the function ceph_mds_auth_match of the component FS File Parser. This manipulation causes null pointer dereference.
This vulnerability is handled as CVE-2026-23189. The attack can only be done within the local network. There is not any exploit available.
It is advisable to upgrade the affected component.
OSV
CVE-2026-23189: In the Linux kernel, the following vulnerability has been resolved: ceph: fix NULL pointer dereference in ceph_mds_auth_match() The CephFS kernel clie
osv·2026-02-14·CVSS 5.5
CVE-2026-23189 [MEDIUM] CVE-2026-23189: In the Linux kernel, the following vulnerability has been resolved: ceph: fix NULL pointer dereference in ceph_mds_auth_match() The CephFS kernel clie
In the Linux kernel, the following vulnerability has been resolved: ceph: fix NULL pointer dereference in ceph_mds_auth_match() The CephFS kernel client has regression starting from 6.18-rc1. We have issue in ceph_mds_auth_match() if fs_name == NULL: const char fs_name = mdsc->fsc->mount_options->mds_namespace; ... if (auth->match.fs_name && strcmp(auth->match.fs_name, fs_name)) { / fsname mismatch, try next one */ return 0; } Patrick Donnelly suggested that: In summary, we should definitely start decoding `fs_name` from the MDSMap and do strict authorizations checks against it. Note that the `-o mds_namespace=foo` should only be used for selecting the file system to mount and nothing else. It's possible no mds_namespace is specified but the kernel will mount the only file system that exis
GHSA
GHSA-r35m-5r25-v2fx: In the Linux kernel, the following vulnerability has been resolved:
ceph: fix NULL pointer dereference in ceph_mds_auth_match()
The CephFS kernel cl
ghsa_unreviewed·2026-02-14
CVE-2026-23189 [MEDIUM] CWE-476 GHSA-r35m-5r25-v2fx: In the Linux kernel, the following vulnerability has been resolved:
ceph: fix NULL pointer dereference in ceph_mds_auth_match()
The CephFS kernel cl
In the Linux kernel, the following vulnerability has been resolved:
ceph: fix NULL pointer dereference in ceph_mds_auth_match()
The CephFS kernel client has regression starting from 6.18-rc1.
We have issue in ceph_mds_auth_match() if fs_name == NULL:
const char fs_name = mdsc->fsc->mount_options->mds_namespace;
...
if (auth->match.fs_name && strcmp(auth->match.fs_name, fs_name)) {
/ fsname mismatch, try next one */
return 0;
}
Patrick Donnelly suggested that: In summary, we should definitely start
decoding `fs_name` from the MDSMap and do strict authorizations checks
against it. Note that the `-o mds_namespace=foo` should only be used for
selecting the file system to mount and nothing else. It's possible
no mds_namespace is specified but the kernel will mount the only
file system that
No detection rules found.
No public exploits indexed.
2026-02-14
Published