{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2024-49936", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-10-21T12:17:06.042Z", "datePublished": "2024-10-21T18:01:57.066Z", "dateUpdated": "2026-08-05T11:40:33.247Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T11:40:33.247Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/xen-netback: prevent UAF in xenvif_flush_hash()\n\nDuring the list_for_each_entry_rcu iteration call of xenvif_flush_hash,\nkfree_rcu does not exist inside the rcu read critical section, so if\nkfree_rcu is called when the rcu grace period ends during the iteration,\nUAF occurs when accessing head->next after the entry becomes free.\n\nTherefore, to solve this, you need to change it to list_for_each_entry_safe." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H", "baseScore": 8.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The trigger is a `XEN_NETIF_CTRL_TYPE_SET_HASH_KEY` request written into the Xen shared-memory control ring by the guest frontend, or control-ring teardown — a local shared-memory interface from a guest VM, not a network protocol. No remote packet path reaches `xenvif_flush_hash()`.\nAC:L - A malicious guest fully controls both sides: it can keep the 64-entry cache populated with distinct flows and issue SET_HASH_KEY control requests in an unbounded tight loop, retrying the RCU-timing window arbitrarily many times per second with no host-side rate limit.\nPR:L - The attacker needs kernel/root control of a guest domU that has been granted a vif by the host toolstack, i.e. a low, host-conferred privilege relative to the vulnerable dom0 component — matching this repo's convention for guest-to-host issues such as CVE-2025-22012.\nUI:N - The guest drives the control ring entirely on its own; no dom0 administrator or user action is required at any point in the path.\nS:C - The vulnerable code executes in the dom0/driver-domain kernel while the attacker resides in an untrusted guest, so successful exploitation crosses the Xen VM/host security boundary.\nC:H - Use-after-free traversal reads `link.next` and entry fields out of freed, reclaimable heap memory in the host kernel, which an attacker who reallocates the slab can leverage into disclosure of host kernel data.\nI:H - After following a stale pointer, `list_del_rcu()` writes through attacker-influenceable `prev->next`/`next->prev` and `kfree_rcu()` is invoked on a bogus pointer, yielding a host-kernel write primitive suitable for control-flow hijacking.\nA:H - Dereferencing freed list memory in a dom0 IRQ-thread context with the cache spinlock held causes an oops or panic of the host kernel, taking down every VM on the machine." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/xen-netback/hash.c" ], "versions": [ { "version": "40d8abdee806d496a60ee607a6d01b1cd7fabaf0", "lessThan": "3c4423b0c4b98213b3438e15061e1d08220e6982", "status": "affected", "versionType": "git" }, { "version": "40d8abdee806d496a60ee607a6d01b1cd7fabaf0", "lessThan": "a7f0073fcd12ed7de185ef2c0af9d0fa1ddef22c", "status": "affected", "versionType": "git" }, { "version": "40d8abdee806d496a60ee607a6d01b1cd7fabaf0", "lessThan": "a0465723b8581cad27164c9073fd780904cd22d4", "status": "affected", "versionType": "git" }, { "version": "40d8abdee806d496a60ee607a6d01b1cd7fabaf0", "lessThan": "efcff6ce7467f01f0753609f420333f3f2ceceda", "status": "affected", "versionType": "git" }, { "version": "40d8abdee806d496a60ee607a6d01b1cd7fabaf0", "lessThan": "143edf098b80669d05245b2f2367dd156a83a2c5", "status": "affected", "versionType": "git" }, { "version": "40d8abdee806d496a60ee607a6d01b1cd7fabaf0", "lessThan": "d408889d4b54f5501e4becc4dbbb9065143fbf4e", "status": "affected", "versionType": "git" }, { "version": "40d8abdee806d496a60ee607a6d01b1cd7fabaf0", "lessThan": "54d8639af5568fc41c0e274fc3ec9cf86c59fcbb", "status": "affected", "versionType": "git" }, { "version": "40d8abdee806d496a60ee607a6d01b1cd7fabaf0", "lessThan": "0fa5e94a1811d68fbffa0725efe6d4ca62c03d12", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/xen-netback/hash.c" ], "versions": [ { "version": "4.7", "status": "affected" }, { "version": "0", "lessThan": "4.7", "status": "unaffected", "versionType": "semver" }, { "version": "5.4.290", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.227", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.168", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.113", "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": "4.7", "versionEndExcluding": "5.4.290" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "5.10.227" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "5.15.168" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "6.1.113" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "6.6.55" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "6.10.14" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "6.11.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.7", "versionEndExcluding": "6.12" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/3c4423b0c4b98213b3438e15061e1d08220e6982" }, { "url": "https://git.kernel.org/stable/c/a7f0073fcd12ed7de185ef2c0af9d0fa1ddef22c" }, { "url": "https://git.kernel.org/stable/c/a0465723b8581cad27164c9073fd780904cd22d4" }, { "url": "https://git.kernel.org/stable/c/efcff6ce7467f01f0753609f420333f3f2ceceda" }, { "url": "https://git.kernel.org/stable/c/143edf098b80669d05245b2f2367dd156a83a2c5" }, { "url": "https://git.kernel.org/stable/c/d408889d4b54f5501e4becc4dbbb9065143fbf4e" }, { "url": "https://git.kernel.org/stable/c/54d8639af5568fc41c0e274fc3ec9cf86c59fcbb" }, { "url": "https://git.kernel.org/stable/c/0fa5e94a1811d68fbffa0725efe6d4ca62c03d12" } ], "title": "net/xen-netback: prevent UAF in xenvif_flush_hash()", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2024-49936", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "version": "2.0.3", "timestamp": "2024-10-22T13:38:23.774447Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2024-10-22T13:38:51.250Z" } }, { "title": "CVE Program Container", "references": [ { "url": "https://lists.debian.org/debian-lts-announce/2025/03/msg00002.html" }, { "url": "https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html" } ], "providerMetadata": { "orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2025-11-03T22:23:20.627Z" } } ] } }