{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-89487", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.713Z", "datePublished": "2026-09-11T19:43:40.776Z", "dateUpdated": "2026-10-19T08:47:37.837Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T08:47:37.837Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nopenvswitch: only skb_tx_error() a packet we are about to drop\n\nqueue_userspace_packet() borrows the packet skb -- it only copies it into\na private netlink message (user_skb) and does not own it; on return\ndo_execute_actions() keeps forwarding it through the flow's remaining\nactions. Its error path nevertheless calls skb_tx_error(skb), which via\nskb_zcopy_clear() does skb_shinfo(skb)->flags &= ~SKBFL_ALL_ZEROCOPY,\nstripping SKBFL_SHARED_FRAG from that live skb (skb_tx_error()'s kerneldoc\nsays \"skb must be freed afterwards\").\n\nFor a MSG_ZEROCOPY skb carrying page-cache frags, SKBFL_SHARED_FRAG is\nwhat makes esp_input() skb_cow_data() before in-place AEAD; once it is\nstripped a later local ESP-in-UDP delivery decrypts in place over pages\nthe sender does not own -- an unprivileged page-cache write (the\n\"Fragnesia\" primitive).\ndo_execute_actions() ignores output_userspace()'s return value, so any\naction after a failed USERSPACE upcall inherits the stripped skb.\n\nMove the skb_tx_error() to the flow-miss drop path - the \"default\"\nbranch of ovs_dp_process_packet()'s switch(error), before kfree_skb().\n\nThe call has been here since commit 36d5fe6a0007 (\"core, nfqueue,\nopenvswitch: Orphan frags in skb_zerocopy and handle errors\") but was\nharmless until esp_input() began relying on SKBFL_SHARED_FRAG to gate\nin-place decrypt; only then did stripping it on a still-forwarded skb\nbecome a page-cache write primitive." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7.8, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - The strip runs only on a locally originated MSG_ZEROCOPY skb that still has a zerocopy uarg (skb_zcopy_clear is a no-op otherwise); NIC-received packets never carry that uarg, and the later in-place ESP decrypt is via a local SA, so a local account is required.\nAC:L - The attacker fully controls the OVS flow (non-last USERSPACE with a PID that makes genlmsg_unicast fail), the MSG_ZEROCOPY send, and the ESP SA/payload; do_execute_actions() ignores the upcall error, so the shared-frag strip and in-place decrypt are deterministic with no race beyond attacker influence.\nPR:L - OVS genetlink families are netnsok and use GENL_UNS_ADMIN_PERM (CAP_NET_ADMIN in the socket user_ns); an unprivileged user can unshare -Urn, create a datapath/flow, enable SO_ZEROCOPY, and install xfrm SAs, while the global page cache remains the corruption target.\nUI:N - The attacker installs the OVS userspace-then-output flow, sends the MSG_ZEROCOPY packet, and completes local ESP-in-UDP delivery without any victim action such as opening a file or mounting a filesystem.\nS:U - The resulting page-cache write is a standard in-kernel memory-corruption/privilege-escalation primitive on the same host; it does not cross a VM hypervisor or IOMMU security boundary.\nC:H - Clearing SKBFL_SHARED_FRAG lets later esp_input() skip skb_cow_data() and AEAD-decrypt in place over page-cache-backed frags, a write primitive into globally cached file/code pages that can be leveraged for arbitrary disclosure.\nI:H - With the shared-frag marker stripped, ESP decrypts attacker-controlled plaintext in place over page-cache pages the sender does not own, yielding the Fragnesia unprivileged write into files the attacker could only read.\nA:H - In-place writes into page-cache-backed or still-mapped zerocopy pages corrupt shared kernel/file state and readily cause oopses, panics, and process crashes; skb_tx_error also completes the uarg while the skb is still in flight." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/openvswitch/datapath.c" ], "versions": [ { "version": "36d5fe6a000790f56039afe26834265db0a3ad4c", "lessThan": "5de5d554141a15b3f1f5c978fd9f7f4fd6d0600a", "status": "affected", "versionType": "git" }, { "version": "36d5fe6a000790f56039afe26834265db0a3ad4c", "lessThan": "48db11e115d1b232edc5591604adc6eda95cd545", "status": "affected", "versionType": "git" }, { "version": "36d5fe6a000790f56039afe26834265db0a3ad4c", "lessThan": "4477222e2916a18e273edc139c955ade6bbb7a69", "status": "affected", "versionType": "git" }, { "version": "36d5fe6a000790f56039afe26834265db0a3ad4c", "lessThan": "4d5c460ef8754be1d43b16dbf02695b008b207d6", "status": "affected", "versionType": "git" }, { "version": "36d5fe6a000790f56039afe26834265db0a3ad4c", "lessThan": "6767d70cf46f65807a6a4c4406a518e6c12e36ae", "status": "affected", "versionType": "git" }, { "version": "36d5fe6a000790f56039afe26834265db0a3ad4c", "lessThan": "e41a59fc056f63a7a1f42788913c53cc48d744aa", "status": "affected", "versionType": "git" }, { "version": "36d5fe6a000790f56039afe26834265db0a3ad4c", "lessThan": "5d85eef222cfd28e73deed7402c100229e8b9e6e", "status": "affected", "versionType": "git" }, { "version": "36d5fe6a000790f56039afe26834265db0a3ad4c", "lessThan": "0dbc2398fca3bb33eda963849f865ddb1b3aa05e", "status": "affected", "versionType": "git" }, { "version": "c5f0c0e7525443add533495e93ba8de6feab2396", "status": "affected", "versionType": "git" }, { "version": "1674b4bf3eea3cac51b70778e89f8025f7cfe695", "status": "affected", "versionType": "git" }, { "version": "3.10.51", "lessThan": "3.11", "status": "affected", "versionType": "semver" }, { "version": "3.12.40", "lessThan": "3.13", "status": "affected", "versionType": "semver" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/openvswitch/datapath.c" ], "versions": [ { "version": "3.14", "status": "affected" }, { "version": "0", "lessThan": "3.14", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.270", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.221", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.188", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.157", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.109", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.50", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.4", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "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": "3.14", "versionEndExcluding": "5.10.270" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.14", "versionEndExcluding": "5.15.221" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.14", "versionEndExcluding": "6.1.188" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.14", "versionEndExcluding": "6.6.157" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.14", "versionEndExcluding": "6.12.109" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.14", "versionEndExcluding": "6.18.50" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.14", "versionEndExcluding": "7.2.4" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.14", "versionEndExcluding": "7.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10.51" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.12.40" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/5de5d554141a15b3f1f5c978fd9f7f4fd6d0600a" }, { "url": "https://git.kernel.org/stable/c/48db11e115d1b232edc5591604adc6eda95cd545" }, { "url": "https://git.kernel.org/stable/c/4477222e2916a18e273edc139c955ade6bbb7a69" }, { "url": "https://git.kernel.org/stable/c/4d5c460ef8754be1d43b16dbf02695b008b207d6" }, { "url": "https://git.kernel.org/stable/c/6767d70cf46f65807a6a4c4406a518e6c12e36ae" }, { "url": "https://git.kernel.org/stable/c/e41a59fc056f63a7a1f42788913c53cc48d744aa" }, { "url": "https://git.kernel.org/stable/c/5d85eef222cfd28e73deed7402c100229e8b9e6e" }, { "url": "https://git.kernel.org/stable/c/0dbc2398fca3bb33eda963849f865ddb1b3aa05e" } ], "title": "openvswitch: only skb_tx_error() a packet we are about to drop", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2026-89487", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "total" } ], "version": "2.0.3", "timestamp": "2026-10-16T19:22:44.373891Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T19:26:40.151Z" } } ] } }