{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2023-53354", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2025-09-16T16:08:59.567Z", "datePublished": "2025-09-17T14:56:44.388Z", "dateUpdated": "2026-08-05T09:13:37.623Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T09:13:37.623Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nskbuff: skb_segment, Call zero copy functions before using skbuff frags\n\nCommit bf5c25d60861 (\"skbuff: in skb_segment, call zerocopy functions\nonce per nskb\") added the call to zero copy functions in skb_segment().\nThe change introduced a bug in skb_segment() because skb_orphan_frags()\nmay possibly change the number of fragments or allocate new fragments\naltogether leaving nrfrags and frag to point to the old values. This can\ncause a panic with stacktrace like the one below.\n\n[ 193.894380] BUG: kernel NULL pointer dereference, address: 00000000000000bc\n[ 193.895273] CPU: 13 PID: 18164 Comm: vh-net-17428 Kdump: loaded Tainted: G O 5.15.123+ #26\n[ 193.903919] RIP: 0010:skb_segment+0xb0e/0x12f0\n[ 194.021892] Call Trace:\n[ 194.027422] \n[ 194.072861] tcp_gso_segment+0x107/0x540\n[ 194.082031] inet_gso_segment+0x15c/0x3d0\n[ 194.090783] skb_mac_gso_segment+0x9f/0x110\n[ 194.095016] __skb_gso_segment+0xc1/0x190\n[ 194.103131] netem_enqueue+0x290/0xb10 [sch_netem]\n[ 194.107071] dev_qdisc_enqueue+0x16/0x70\n[ 194.110884] __dev_queue_xmit+0x63b/0xb30\n[ 194.121670] bond_start_xmit+0x159/0x380 [bonding]\n[ 194.128506] dev_hard_start_xmit+0xc3/0x1e0\n[ 194.131787] __dev_queue_xmit+0x8a0/0xb30\n[ 194.138225] macvlan_start_xmit+0x4f/0x100 [macvlan]\n[ 194.141477] dev_hard_start_xmit+0xc3/0x1e0\n[ 194.144622] sch_direct_xmit+0xe3/0x280\n[ 194.147748] __dev_queue_xmit+0x54a/0xb30\n[ 194.154131] tap_get_user+0x2a8/0x9c0 [tap]\n[ 194.157358] tap_sendmsg+0x52/0x8e0 [tap]\n[ 194.167049] handle_tx_zerocopy+0x14e/0x4c0 [vhost_net]\n[ 194.173631] handle_tx+0xcd/0xe0 [vhost_net]\n[ 194.176959] vhost_worker+0x76/0xb0 [vhost]\n[ 194.183667] kthread+0x118/0x140\n[ 194.190358] ret_from_fork+0x1f/0x30\n[ 194.193670] \n\nIn this case calling skb_orphan_frags() updated nr_frags leaving nrfrags\nlocal variable in skb_segment() stale. This resulted in the code hitting\ni >= nrfrags prematurely and trying to move to next frag_skb using\nlist_skb pointer, which was NULL, and caused kernel panic. Move the call\nto zero copy functions before using frags and nr_frags." } ], "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 bug is only reachable on TX skbs with zerocopy user frags (MSG_ZEROCOPY or vhost_net handle_tx_zerocopy); received remote packets do not carry skb_zcopy state, so skb_orphan_frags() is a no-op and cannot trigger the stale-frag path.\nAC:L - An attacker controls SO_ZEROCOPY/MSG_ZEROCOPY iov layout (hence how skb_copy_ubufs() changes nr_frags) and can force software GSO via netem/tbf in an unprivileged user+net namespace or any non-TSO egress path, making the trigger reliable.\nPR:L - SO_ZEROCOPY has no capability check, and CAP_NET_ADMIN needed to attach netem or disable TSO is available via unprivileged user namespaces; no real init-namespace root is required.\nUI:N - The attacker triggers the bug entirely through their own socket sends and optional qdisc configuration; no victim interaction is required.\nS:U - Corruption and crash occur in host kernel skbuff/GSO state within the same kernel security authority; this is standard local kernel memory corruption, not a VM/IOMMU/sandbox boundary escape.\nC:H - When skb_copy_ubufs() reduces nr_frags, skb_segment continues with a stale larger nfrags and re-refs frag slots whose pages were already unreferenced, yielding a UAF that can disclose kernel memory.\nI:H - The same stale-frag UAF (and dangling frag pointer if skb_unclone relocates shinfo) is heap memory corruption exploitable for arbitrary write/control-flow hijacking per UAF scoring guidance.\nA:H - The reported impact is a kernel NULL pointer dereference panic in skb_segment, and the UAF paths also cause oops/panic-level denial of service." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/core/skbuff.c" ], "versions": [ { "version": "bf5c25d608613eaf4dcdba5a9cac5b2afe67d635", "lessThan": "fcab3f661dbfd88e27ddbbe65368f3fa2d823175", "status": "affected", "versionType": "git" }, { "version": "bf5c25d608613eaf4dcdba5a9cac5b2afe67d635", "lessThan": "d44403ec0676317b7f7edf2a035bb219fee3304e", "status": "affected", "versionType": "git" }, { "version": "bf5c25d608613eaf4dcdba5a9cac5b2afe67d635", "lessThan": "8836c266201c29a5acb4f582227686f47b65ad61", "status": "affected", "versionType": "git" }, { "version": "bf5c25d608613eaf4dcdba5a9cac5b2afe67d635", "lessThan": "d5790386595d06ea9decfd9ba5f1ea48cf09aa02", "status": "affected", "versionType": "git" }, { "version": "bf5c25d608613eaf4dcdba5a9cac5b2afe67d635", "lessThan": "04c3eee4e13f60bf6f9a366ad39f88a01a57166e", "status": "affected", "versionType": "git" }, { "version": "bf5c25d608613eaf4dcdba5a9cac5b2afe67d635", "lessThan": "f99006e840a4dbc8f5a34cecc6b5b26c73ef49bb", "status": "affected", "versionType": "git" }, { "version": "bf5c25d608613eaf4dcdba5a9cac5b2afe67d635", "lessThan": "6c26ed3c6abe86ddab0510529000b970b05c9b40", "status": "affected", "versionType": "git" }, { "version": "bf5c25d608613eaf4dcdba5a9cac5b2afe67d635", "lessThan": "2ea35288c83b3d501a88bc17f2df8f176b5cc96f", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/core/skbuff.c" ], "versions": [ { "version": "4.16", "status": "affected" }, { "version": "0", "lessThan": "4.16", "status": "unaffected", "versionType": "semver" }, { "version": "4.19.295", "lessThanOrEqual": "4.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.4.257", "lessThanOrEqual": "5.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.195", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.132", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.53", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.4.16", "lessThanOrEqual": "6.4.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.5.3", "lessThanOrEqual": "6.5.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6", "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": "4.16", "versionEndExcluding": "4.19.295" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "5.4.257" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "5.10.195" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "5.15.132" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "6.1.53" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "6.4.16" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "6.5.3" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.16", "versionEndExcluding": "6.6" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/fcab3f661dbfd88e27ddbbe65368f3fa2d823175" }, { "url": "https://git.kernel.org/stable/c/d44403ec0676317b7f7edf2a035bb219fee3304e" }, { "url": "https://git.kernel.org/stable/c/8836c266201c29a5acb4f582227686f47b65ad61" }, { "url": "https://git.kernel.org/stable/c/d5790386595d06ea9decfd9ba5f1ea48cf09aa02" }, { "url": "https://git.kernel.org/stable/c/04c3eee4e13f60bf6f9a366ad39f88a01a57166e" }, { "url": "https://git.kernel.org/stable/c/f99006e840a4dbc8f5a34cecc6b5b26c73ef49bb" }, { "url": "https://git.kernel.org/stable/c/6c26ed3c6abe86ddab0510529000b970b05c9b40" }, { "url": "https://git.kernel.org/stable/c/2ea35288c83b3d501a88bc17f2df8f176b5cc96f" } ], "title": "skbuff: skb_segment, Call zero copy functions before using skbuff frags", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "cvssV3_1": { "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" } }, { "other": { "type": "ssvc", "content": { "id": "CVE-2023-53354", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "no" }, { "Technical Impact": "partial" } ], "version": "2.0.3", "timestamp": "2026-01-14T18:42:19.915192Z" } } } ], "problemTypes": [ { "descriptions": [ { "lang": "en", "type": "CWE", "cweId": "CWE-476", "description": "CWE-476 NULL Pointer Dereference" } ] } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-01-14T18:43:04.063Z" } } ] } }