CVE-2022-49348
MediumIn the Linux kernel, the following vulnerability has been resolved: ext4: filter out EXT4_FC_REPLAY from on-disk superblock field s_state The EXT4_FC_REPLAY bit in sbi->s_mount_state is used to indicate that we are in the middle of replay the fast commit journal. This was actually a mistake, since the sbi->s_mount_info is initialized from es->s_state. Arguably s_mount_state is misleadingly named, but the name is historical --- s_mount_state and s_state dates back to ext2. What should have been used is the ext4_{set,clear,test}_mount_flag() inline functions, which sets EXT4_MF_* bits in sbi->s_mount_flags. The problem with using EXT4_FC_REPLAY is that a maliciously corrupted superblock could result in EXT4_FC_REPLAY getting set in s_mount_state. This bypasses some sanity checks, and this can trigger a BUG() in ext4_es_cache_extent(). As a easy-to-backport-fix, filter out the EXT4_FC_REPLAY bit for now. We should eventually transition away from EXT4_FC_REPLAY to something like EXT4_MF_REPLAY.
CVSS 3.1 score
5.5
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Affected versions
Linux kernel versions
5.10
and later are affected. Fixed in
5.10.121,
5.15.46,
5.17.14,
5.18.3,
5.19
and their respective stable series.
References
The following references provide additional information about CVE-2022-49348 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.
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PatchKernel patch commithttps://git.kernel.org/stable/c/55b4dbb29054a05d839562f6d635ce05669b016d
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PatchKernel patch commithttps://git.kernel.org/stable/c/af2f1932743fb52ebcb008ad7ac500d9df0aa796
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PatchKernel patch commithttps://git.kernel.org/stable/c/b99fd73418350dea360da8311e87a6a7b0e15a4c
Frequently asked questions
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What is CVE-2022-49348?
CVE-2022-49348 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 . It affects Linux kernel versions from 5.10 onward and has been patched in 5.10.121, 5.15.46, 5.17.14 and others. CVE-2022-49348 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
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What is the CVSS score for CVE-2022-49348?
CVE-2022-49348 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H. -
Is there a patch available for CVE-2022-49348?
Yes — CVE-2022-49348 has been patched. Fixed versions include 5.10.121, 5.15.46, 5.17.14 and others. If you are running Linux kernel 5.10 or later up to the fix versions, apply the relevant patch for your kernel branch.
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Is CVE-2022-49348 actively exploited?
No — CVE-2022-49348 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.