CVE-2022-49526

{"id": "CVE-2022-49526", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.5, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 1.8}]}, "published": "2025-02-26T07:01:28.593", "references": [{"url": "https://git.kernel.org/stable/c/0959aa00f9765bd8c654b1365012e41b51c733cc", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/27f672af28a8e9b783ff7f0eaf7ef2fbd5a2f4ba", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/422e8f7ba1e08c8e0e88d375bcb550bc2bbfe96d", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/cf9392282a2cf5a8d83dd1c5aa1a097e12f172bc", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/d8f1558e1daf54f53a90b4c5700ae3e3a4b13412", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/e68cb83a57a458b01c9739e2ad9cb70b04d1e6d2", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/e69e93120f6219b9cc4fba3b515b6ababd8548aa", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "CWE-476"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmd/bitmap: don't set sb values if can't pass sanity check\n\nIf bitmap area contains invalid data, kernel will crash then mdadm\ntriggers \"Segmentation fault\".\nThis is cluster-md speical bug. In non-clustered env, mdadm will\nhandle broken metadata case. In clustered array, only kernel space\nhandles bitmap slot info. But even this bug only happened in clustered\nenv, current sanity check is wrong, the code should be changed.\n\nHow to trigger: (faulty injection)\n\ndd if=/dev/zero bs=1M count=1 oflag=direct of=/dev/sda\ndd if=/dev/zero bs=1M count=1 oflag=direct of=/dev/sdb\nmdadm -C /dev/md0 -b clustered -e 1.2 -n 2 -l mirror /dev/sda /dev/sdb\nmdadm -Ss\necho aaa > magic.txt\n == below modifying slot 2 bitmap data ==\ndd if=magic.txt of=/dev/sda seek=16384 bs=1 count=3 <== destroy magic\ndd if=/dev/zero of=/dev/sda seek=16436 bs=1 count=4 <== ZERO chunksize\nmdadm -A /dev/md0 /dev/sda /dev/sdb\n == kernel crashes. mdadm outputs \"Segmentation fault\" ==\n\nReason of kernel crash:\n\nIn md_bitmap_read_sb (called by md_bitmap_create), bad bitmap magic didn't\nblock chunksize assignment, and zero value made DIV_ROUND_UP_SECTOR_T()\ntrigger \"divide error\".\n\nCrash log:\n\nkernel: md: md0 stopped.\nkernel: md/raid1:md0: not clean -- starting background reconstruction\nkernel: md/raid1:md0: active with 2 out of 2 mirrors\nkernel: dlm: ... ...\nkernel: md-cluster: Joined cluster 44810aba-38bb-e6b8-daca-bc97a0b254aa slot 1\nkernel: md0: invalid bitmap file superblock: bad magic\nkernel: md_bitmap_copy_from_slot can't get bitmap from slot 2\nkernel: md-cluster: Could not gather bitmaps from slot 2\nkernel: divide error: 0000 [#1] SMP NOPTI\nkernel: CPU: 0 PID: 1603 Comm: mdadm Not tainted 5.14.6-1-default\nkernel: Hardware name: QEMU Standard PC (i440FX + PIIX, 1996)\nkernel: RIP: 0010:md_bitmap_create+0x1d1/0x850 [md_mod]\nkernel: RSP: 0018:ffffc22ac0843ba0 EFLAGS: 00010246\nkernel: ... ...\nkernel: Call Trace:\nkernel: ? dlm_lock_sync+0xd0/0xd0 [md_cluster 77fe..7a0]\nkernel: md_bitmap_copy_from_slot+0x2c/0x290 [md_mod 24ea..d3a]\nkernel: load_bitmaps+0xec/0x210 [md_cluster 77fe..7a0]\nkernel: md_bitmap_load+0x81/0x1e0 [md_mod 24ea..d3a]\nkernel: do_md_run+0x30/0x100 [md_mod 24ea..d3a]\nkernel: md_ioctl+0x1290/0x15a0 [md_mod 24ea....d3a]\nkernel: ? mddev_unlock+0xaa/0x130 [md_mod 24ea..d3a]\nkernel: ? blkdev_ioctl+0xb1/0x2b0\nkernel: block_ioctl+0x3b/0x40\nkernel: __x64_sys_ioctl+0x7f/0xb0\nkernel: do_syscall_64+0x59/0x80\nkernel: ? exit_to_user_mode_prepare+0x1ab/0x230\nkernel: ? syscall_exit_to_user_mode+0x18/0x40\nkernel: ? do_syscall_64+0x69/0x80\nkernel: entry_SYSCALL_64_after_hwframe+0x44/0xae\nkernel: RIP: 0033:0x7f4a15fa722b\nkernel: ... ...\nkernel: ---[ end trace 8afa7612f559c868 ]---\nkernel: RIP: 0010:md_bitmap_create+0x1d1/0x850 [md_mod]"}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: md/bitmap: no establezca valores sb si no puede pasar la comprobaci\u00f3n de cordura. Si el \u00e1rea de mapa de bits contiene datos no v\u00e1lidos, el kernel se bloquear\u00e1 y mdadm activar\u00e1 \"Error de segmentaci\u00f3n\". Este es un error especial de cluster-md. En un entorno no agrupado, mdadm gestionar\u00e1 el caso de metadatos da\u00f1ados. En una matriz agrupada, solo el espacio del kernel getiona la informaci\u00f3n de la ranura de mapa de bits. Pero incluso este error solo ocurri\u00f3 en un entorno agrupado, la comprobaci\u00f3n de cordura actual es incorrecta, el c\u00f3digo debe cambiarse. C\u00f3mo activar: (inyecci\u00f3n defectuosa) dd if=/dev/zero bs=1M count=1 oflag=direct of=/dev/sda dd if=/dev/zero bs=1M count=1 oflag=direct of=/dev/sdb mdadm -C /dev/md0 -b clustered -e 1.2 -n 2 -l mirror /dev/sda /dev/sdb mdadm -Ss echo aaa &gt; magic.txt == below modifying slot 2 bitmap data == dd if=magic.txt of=/dev/sda seek=16384 bs=1 count=3 &lt;== destroy magic dd if=/dev/zero of=/dev/sda seek=16436 bs=1 count=4 &lt;== ZERO chunksize mdadm -A /dev/md0 /dev/sda /dev/sdb == kernel crashes. mdadm outputs \"Segmentation fault\" == Reason of kernel crash: In md_bitmap_read_sb (called by md_bitmap_create), bad bitmap magic didn't block chunksize assignment, and zero value made DIV_ROUND_UP_SECTOR_T() trigger \"divide error\". Crash log: kernel: md: md0 stopped. kernel: md/raid1:md0: not clean -- starting background reconstruction kernel: md/raid1:md0: active with 2 out of 2 mirrors kernel: dlm: ... ... kernel: md-cluster: Joined cluster 44810aba-38bb-e6b8-daca-bc97a0b254aa slot 1 kernel: md0: invalid bitmap file superblock: bad magic kernel: md_bitmap_copy_from_slot can't get bitmap from slot 2 kernel: md-cluster: Could not gather bitmaps from slot 2 kernel: divide error: 0000 [#1] SMP NOPTI kernel: CPU: 0 PID: 1603 Comm: mdadm Not tainted 5.14.6-1-default kernel: Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) kernel: RIP: 0010:md_bitmap_create+0x1d1/0x850 [md_mod] kernel: RSP: 0018:ffffc22ac0843ba0 EFLAGS: 00010246 kernel: ... ... kernel: Call Trace: kernel: ? dlm_lock_sync+0xd0/0xd0 [md_cluster 77fe..7a0] kernel: md_bitmap_copy_from_slot+0x2c/0x290 [md_mod 24ea..d3a] kernel: load_bitmaps+0xec/0x210 [md_cluster 77fe..7a0] kernel: md_bitmap_load+0x81/0x1e0 [md_mod 24ea..d3a] kernel: do_md_run+0x30/0x100 [md_mod 24ea..d3a] kernel: md_ioctl+0x1290/0x15a0 [md_mod 24ea....d3a] kernel: ? mddev_unlock+0xaa/0x130 [md_mod 24ea..d3a] kernel: ? blkdev_ioctl+0xb1/0x2b0 kernel: block_ioctl+0x3b/0x40 kernel: __x64_sys_ioctl+0x7f/0xb0 kernel: do_syscall_64+0x59/0x80 kernel: ? exit_to_user_mode_prepare+0x1ab/0x230 kernel: ? syscall_exit_to_user_mode+0x18/0x40 kernel: ? do_syscall_64+0x69/0x80 kernel: entry_SYSCALL_64_after_hwframe+0x44/0xae kernel: RIP: 0033:0x7f4a15fa722b kernel: ... ... kernel: ---[ end trace 8afa7612f559c868 ]--- kernel: RIP: 0010:md_bitmap_create+0x1d1/0x850 [md_mod] "}], "lastModified": "2025-10-21T12:05:58.860", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "D050F8AE-EE13-436A-B863-56AD3787ECFB", "versionEndExcluding": "4.19.247"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "3EC49633-14DE-4EBD-BB80-76AE2E3EABB9", "versionEndExcluding": "5.4.198", "versionStartIncluding": "4.20"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "34ACD872-E5BC-401C-93D5-B357A62426E0", "versionEndExcluding": "5.10.121", "versionStartIncluding": "5.5"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "20D41697-0E8B-4B7D-8842-F17BF2AA21E1", "versionEndExcluding": "5.15.46", "versionStartIncluding": "5.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "15E2DD33-2255-4B76-9C15-04FF8CBAB252", "versionEndExcluding": "5.17.14", "versionStartIncluding": "5.16"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "8E122216-2E9E-4B3E-B7B8-D575A45BA3C2", "versionEndExcluding": "5.18.3", "versionStartIncluding": "5.18"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}