{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2024-49960", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-10-21T12:17:06.049Z", "datePublished": "2024-10-21T18:02:13.119Z", "dateUpdated": "2026-08-05T11:40:42.935Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:40:42.935Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\next4: fix timer use-after-free on failed mount\n\nSyzbot has found an ODEBUG bug in ext4_fill_super\n\nThe del_timer_sync function cancels the s_err_report timer,\nwhich reminds about filesystem errors daily. We should\nguarantee the timer is no longer active before kfree(sbi).\n\nWhen filesystem mounting fails, the flow goes to failed_mount3,\nwhere an error occurs when ext4_stop_mmpd is called, causing\na read I/O failure. This triggers the ext4_handle_error function\nthat ultimately re-arms the timer,\nleaving the s_err_report timer active before kfree(sbi) is called.\n\nFix the issue by canceling the s_err_report timer after calling ext4_stop_mmpd." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The bug is triggered by mounting a crafted ext4 image via the mount(2)/fsconfig(2) syscall path, which requires local system access to the block device or image file. There is no remote or network-facing entry point into `ext4_fill_super()`.\nAC:L - The attacker fully controls the crafted image: enabling the MMP feature starts kmmpd, and planting a later-stage mount failure plus an unreadable/corrupt MMP block deterministically drives `ext4_stop_mmpd()` → `ext4_error_err()` → `mod_timer()` after the timer was already cancelled. syzbot reproduced it reliably; no race or uncontrolled memory-layout condition is involved.\nPR:N - The attacker supplies only a malicious filesystem image or removable device and needs no account on the target; the privileged mount is performed by the victim or by an automounter (udisks2/autofs) acting on their behalf.\nUI:R - Because ext4 is not FS_USERNS_MOUNT, someone with CAP_SYS_ADMIN (or a desktop automount daemon reacting to inserted media) must actually mount the attacker-supplied image for the failed-mount cleanup path to run.\nS:U - The freed `ext4_sb_info` and the stale timer both live in the kernel's own security authority; exploitation yields kernel-level compromise but does not cross a hypervisor, IOMMU, or sandbox boundary.\nC:H - The armed `s_err_report` timer_list points into freed slab memory, so reallocating that object gives the attacker a use-after-free with control over the freed contents, which is leverageable into arbitrary kernel memory disclosure.\nI:H - The stale timer wheel entry is both an hlist_node and a `->function` pointer read out of attacker-reallocatable memory, giving list-corruption write and control-flow-hijack primitives executed from softirq context.\nA:H - The use-after-free reliably produces an ODEBUG/KASAN splat and, in production kernels, timer-wheel corruption leading to an oops or panic when the freed object is reused or the timer expires." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/ext4/super.c" ], "versions": [ { "version": "5e4f5138bd8522ebe231a137682d3857209a2c07", "lessThan": "7aac0c17a8cdf4a3236991c1e60435c6a984076c", "status": "affected", "versionType": "git" }, { "version": "618f003199c6188e01472b03cdbba227f1dc5f24", "lessThan": "22e9b83f0f33bc5a7a3181769d1dccbf021f5b04", "status": "affected", "versionType": "git" }, { "version": "618f003199c6188e01472b03cdbba227f1dc5f24", "lessThan": "cf3196e5e2f36cd80dab91ffae402e13935724bc", "status": "affected", "versionType": "git" }, { "version": "618f003199c6188e01472b03cdbba227f1dc5f24", "lessThan": "9203817ba46ebba7c865c8de2aba399537b6e891", "status": "affected", "versionType": "git" }, { "version": "618f003199c6188e01472b03cdbba227f1dc5f24", "lessThan": "fa78fb51d396f4f2f80f8e96a3b1516f394258be", "status": "affected", "versionType": "git" }, { "version": "618f003199c6188e01472b03cdbba227f1dc5f24", "lessThan": "b85569585d0154d4db1e4f9e3e6a4731d407feb0", "status": "affected", "versionType": "git" }, { "version": "618f003199c6188e01472b03cdbba227f1dc5f24", "lessThan": "0ce160c5bdb67081a62293028dc85758a8efb22a", "status": "affected", "versionType": "git" }, { "version": "cecfdb9cf9a700d1037066173abac0617f6788df", "status": "affected", "versionType": "git" }, { "version": "eb7b40d9d3785f7a131fb0b1f89bb6efa46c1833", "status": "affected", "versionType": "git" }, { "version": "5.10.51", "lessThan": "5.10.237", "status": "affected", "versionType": "semver" }, { "version": "5.12.18", "lessThan": "5.13", "status": "affected", "versionType": "semver" }, { "version": "5.13.3", "lessThan": "5.14", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "fs/ext4/super.c" ], "versions": [ { "version": "5.14", "status": "affected" }, { "version": "0", "lessThan": "5.14", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.237", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.181", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.118", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.55", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.10.14", "lessThanOrEqual": "6.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.11.3", "lessThanOrEqual": "6.11.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix" } ] } ], "cpeApplicability": [ { "nodes": [ { "operator": "OR", "negate": false, "cpeMatch": [ { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.10.51", "versionEndExcluding": "5.10.237" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.14", "versionEndExcluding": "5.15.181" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.14", "versionEndExcluding": "6.1.118" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.14", "versionEndExcluding": "6.6.55" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.14", "versionEndExcluding": "6.10.14" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.14", "versionEndExcluding": "6.11.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.14", "versionEndExcluding": "6.12" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.12.18" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.13.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/7aac0c17a8cdf4a3236991c1e60435c6a984076c" }, { "url": "https://git.kernel.org/stable/c/22e9b83f0f33bc5a7a3181769d1dccbf021f5b04" }, { "url": "https://git.kernel.org/stable/c/cf3196e5e2f36cd80dab91ffae402e13935724bc" }, { "url": "https://git.kernel.org/stable/c/9203817ba46ebba7c865c8de2aba399537b6e891" }, { "url": "https://git.kernel.org/stable/c/fa78fb51d396f4f2f80f8e96a3b1516f394258be" }, { "url": "https://git.kernel.org/stable/c/b85569585d0154d4db1e4f9e3e6a4731d407feb0" }, { "url": "https://git.kernel.org/stable/c/0ce160c5bdb67081a62293028dc85758a8efb22a" } ], "title": "ext4: fix timer use-after-free on failed mount", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2024-49960", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "version": "2.0.3", "timestamp": "2024-10-22T13:35:13.994206Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-10-22T13:38:47.803Z" } }, { "title": "CVE Program Container", "references": [ { "url": "https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html" }, { "url": "https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html" } ], "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2025-11-03T22:23:41.082Z" } } ] } }