{"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"}}]}}