CVE-2026-43273

Description

In the Linux kernel, the following vulnerability has been resolved: ceph: supply snapshot context in ceph_zero_partial_object() The ceph_zero_partial_object function was missing proper snapshot context for its OSD write operations, which could lead to data inconsistencies in snapshots. Reproducer: ../src/vstart.sh --new -x --localhost --bluestore ./bin/ceph auth caps client.fs_a mds 'allow rwps fsname=a' mon 'allow r fsname=a' osd 'allow rw tag cephfs data=a' mount -t ceph [email protected]=/ /mnt/mycephfs/ -o conf=./ceph.conf dd if=/dev/urandom of=/mnt/mycephfs/foo bs=64K count=1 mkdir /mnt/mycephfs/.snap/snap1 md5sum /mnt/mycephfs/.snap/snap1/foo fallocate -p -o 0 -l 4096 /mnt/mycephfs/foo echo 3 > /proc/sys/vm/drop/caches md5sum /mnt/mycephfs/.snap/snap1/foo # get different md5sum!!

CVSS Details

CVSS Score

5.5

Severity

MEDIUM

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Configurations (Affected Products)

cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* - VULNERABLE

Linux Kernel (修复前版本，具体见Git提交记录)

PoC / Exploit Code

⚠ For Security Research Only

The following code is for security research and authorized testing only.

python

#!/bin/bash # Reproducer for CVE-2026-43273 # Setup environment and mount CephFS ../src/vstart.sh --new -x --localhost --bluestore ./bin/ceph auth caps client.fs_a mds 'allow rwps fsname=a' mon 'allow r fsname=a' osd 'allow rw tag cephfs data=a' mount -t ceph [email protected]=/ /mnt/mycephfs/ -o conf=./ceph.conf # Write data and create snapshot dd if=/dev/urandom of=/mnt/mycephfs/foo bs=64K count=1 mkdir /mnt/mycephfs/.snap/snap1 md5sum /mnt/mycephfs/.snap/snap1/foo # Trigger vulnerability using fallocate to punch hole fallocate -p -o 0 -l 4096 /mnt/mycephfs/foo # Clear cache and verify data integrity echo 3 > /proc/sys/vm/drop/caches md5sum /mnt/mycephfs/.snap/snap1/foo # Expected: different md5sum indicating corruption

References

[1] CVE.org https://www.cve.org/CVERecord?id=CVE-2026-43273
[2] NVD NIST https://nvd.nist.gov/vuln/detail/CVE-2026-43273
[3] CVE Details https://www.cvedetails.com/cve/CVE-2026-43273/
[4] VulDB https://vuldb.com/cve/CVE-2026-43273
[5] https://git.kernel.org/stable/c/36673344b41c31fb502dd0d0113cec1aa96f581e
[6] https://git.kernel.org/stable/c/4097e70fc543cca72982854108a32f6ae924e727
[7] https://git.kernel.org/stable/c/531a76c5a2e44264cee8a70121e63eb28c1ba728
[8] https://git.kernel.org/stable/c/5788b742007f53406049bef917833a71ddd43f60
[9] https://git.kernel.org/stable/c/69e59a87bab0ea31ab2a584fc65e12dafacf8953
[10] https://git.kernel.org/stable/c/757873abfc8ea38592582180aed0f57f0f0cb07a
[11] https://git.kernel.org/stable/c/9efa154609cdb658f51c7d76b30a09f7e6485250
[12] https://git.kernel.org/stable/c/f16bd3fa74a2084ee7e16a8a2be7e7399b970907

Raw JSON Data

JSON

{"cve": {"id": "CVE-2026-43273", "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "published": "2026-05-06T12:16:48.543", "lastModified": "2026-05-08T20:01:19.023", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nceph: supply snapshot context in ceph_zero_partial_object()\n\nThe ceph_zero_partial_object function was missing proper snapshot\ncontext for its OSD write operations, which could lead to data\ninconsistencies in snapshots.\n\nReproducer:\n../src/vstart.sh --new -x --localhost --bluestore\n./bin/ceph auth caps client.fs_a mds 'allow rwps fsname=a' mon 'allow r fsname=a' osd 'allow rw tag cephfs data=a'\nmount -t ceph [email protected]=/ /mnt/mycephfs/ -o conf=./ceph.conf\ndd if=/dev/urandom of=/mnt/mycephfs/foo bs=64K count=1\nmkdir /mnt/mycephfs/.snap/snap1\nmd5sum /mnt/mycephfs/.snap/snap1/foo\nfallocate -p -o 0 -l 4096 /mnt/mycephfs/foo\necho 3 > /proc/sys/vm/drop/caches\nmd5sum /mnt/mycephfs/.snap/snap1/foo # get different md5sum!!"}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "baseScore": 5.5, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Primary", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.12", "versionEndExcluding": "5.10.252", "matchCriteriaId": "360F987A-1B41-4351-A04D-22A93596C979"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "5.15.202", "matchCriteriaId": "4002FC2B-1456-4666-B240-0EBF590C4671"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.16", "versionEndExcluding": "6.1.165", "matchCriteriaId": "797C7F46-D0BE-4FB8-A502-C5EF8E6B6654"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.2", "versionEndExcluding": "6.6.128", "matchCriteriaId": "851E9353-6C09-4CC9-877E-E09DB164A3C2"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.7", "versionEndExcluding": "6.12.75", "matchCriteriaId": "BCE16369-98ED-41CF-8995-DFDC10B288D2"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.13", "versionEndExcluding": "6.18.16", "matchCriteriaId": "B4B8CDA9-BADF-4CF5-8B3B-702DE8EEA40B"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "6.19", "versionEndExcluding": "6.19.6", "matchCriteriaId": "373EEEDA-FAA1-4FB4-B6ED-DB4DD99DBE67"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/36673344b41c31fb502dd0d0113cec1aa96f581e", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/4097e70fc543cca72982854108a32f6ae924e727", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/531a76c5a2e44264cee8a70121e63eb28c1ba728", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/5788b742007f53406049bef917833a71ddd43f60", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/69e59a87bab0ea31ab2a584fc65e12dafacf8953", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/757873abfc8ea38592582180aed0f57f0f0cb07a", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/9efa154609cdb658f51c7d76b30a09f7e6485250", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}, {"url": "https://git.kernel.org/stable/c/f16bd3fa74a2084ee7e16a8a2be7e7399b970907", "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"]}]}}