{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-23449", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-01-13T15:37:46.020Z", "datePublished": "2026-04-03T15:15:32.150Z", "dateUpdated": "2026-08-05T12:21:49.802Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:21:49.802Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: teql: Fix double-free in teql_master_xmit\n\nWhenever a TEQL devices has a lockless Qdisc as root, qdisc_reset should\nbe called using the seq_lock to avoid racing with the datapath. Failure\nto do so may cause crashes like the following:\n\n[ 238.028993][ T318] BUG: KASAN: double-free in skb_release_data (net/core/skbuff.c:1139)\n[ 238.029328][ T318] Free of addr ffff88810c67ec00 by task poc_teql_uaf_ke/318\n[ 238.029749][ T318]\n[ 238.029900][ T318] CPU: 3 UID: 0 PID: 318 Comm: poc_teql_ke Not tainted 7.0.0-rc3-00149-ge5b31d988a41 #704 PREEMPT(full)\n[ 238.029906][ T318] Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011\n[ 238.029910][ T318] Call Trace:\n[ 238.029913][ T318] \n[ 238.029916][ T318] dump_stack_lvl (lib/dump_stack.c:122)\n[ 238.029928][ T318] print_report (mm/kasan/report.c:379 mm/kasan/report.c:482)\n[ 238.029940][ T318] ? skb_release_data (net/core/skbuff.c:1139)\n[ 238.029944][ T318] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)\n...\n[ 238.029957][ T318] ? skb_release_data (net/core/skbuff.c:1139)\n[ 238.029969][ T318] kasan_report_invalid_free (mm/kasan/report.c:221 mm/kasan/report.c:563)\n[ 238.029979][ T318] ? skb_release_data (net/core/skbuff.c:1139)\n[ 238.029989][ T318] check_slab_allocation (mm/kasan/common.c:231)\n[ 238.029995][ T318] kmem_cache_free (mm/slub.c:2637 (discriminator 1) mm/slub.c:6168 (discriminator 1) mm/slub.c:6298 (discriminator 1))\n[ 238.030004][ T318] skb_release_data (net/core/skbuff.c:1139)\n...\n[ 238.030025][ T318] sk_skb_reason_drop (net/core/skbuff.c:1256)\n[ 238.030032][ T318] pfifo_fast_reset (./include/linux/ptr_ring.h:171 ./include/linux/ptr_ring.h:309 ./include/linux/skb_array.h:98 net/sched/sch_generic.c:827)\n[ 238.030039][ T318] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)\n...\n[ 238.030054][ T318] qdisc_reset (net/sched/sch_generic.c:1034)\n[ 238.030062][ T318] teql_destroy (./include/linux/spinlock.h:395 net/sched/sch_teql.c:157)\n[ 238.030071][ T318] __qdisc_destroy (./include/net/pkt_sched.h:328 net/sched/sch_generic.c:1077)\n[ 238.030077][ T318] qdisc_graft (net/sched/sch_api.c:1062 net/sched/sch_api.c:1053 net/sched/sch_api.c:1159)\n[ 238.030089][ T318] ? __pfx_qdisc_graft (net/sched/sch_api.c:1091)\n[ 238.030095][ T318] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)\n[ 238.030102][ T318] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)\n[ 238.030106][ T318] ? srso_alias_return_thunk (arch/x86/lib/retpoline.S:221)\n[ 238.030114][ T318] tc_get_qdisc (net/sched/sch_api.c:1529 net/sched/sch_api.c:1556)\n...\n[ 238.072958][ T318] Allocated by task 303 on cpu 5 at 238.026275s:\n[ 238.073392][ T318] kasan_save_stack (mm/kasan/common.c:58)\n[ 238.073884][ T318] kasan_save_track (mm/kasan/common.c:64 (discriminator 5) mm/kasan/common.c:79 (discriminator 5))\n[ 238.074230][ T318] __kasan_slab_alloc (mm/kasan/common.c:369)\n[ 238.074578][ T318] kmem_cache_alloc_node_noprof (./include/linux/kasan.h:253 mm/slub.c:4542 mm/slub.c:4869 mm/slub.c:4921)\n[ 238.076091][ T318] kmalloc_reserve (net/core/skbuff.c:616 (discriminator 107))\n[ 238.076450][ T318] __alloc_skb (net/core/skbuff.c:713)\n[ 238.076834][ T318] alloc_skb_with_frags (./include/linux/skbuff.h:1383 net/core/skbuff.c:6763)\n[ 238.077178][ T318] sock_alloc_send_pskb (net/core/sock.c:2997)\n[ 238.077520][ T318] packet_sendmsg (net/packet/af_packet.c:2926 net/packet/af_packet.c:3019 net/packet/af_packet.c:3108)\n[ 238.081469][ T318]\n[ 238.081870][ T318] Freed by task 299 on cpu 1 at 238.028496s:\n[ 238.082761][ T318] kasan_save_stack (mm/kasan/common.c:58)\n[ 238.083481][ T318] kasan_save_track (mm/kasan/common.c:64 (discriminator 5) mm/kasan/common.c:79 (discriminator 5))\n[ 238.085348][ T318] kasan_save_free_info (mm/kasan/generic.c:587 (discriminator 1))\n[ 238.085900][ T318] __kasan_slab_free (mm/\n---truncated---" } ], "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 vulnerable path is reached through local packet transmission and RTNETLINK tc/qdisc operations against TEQL; remote packets alone cannot create/delete the qdiscs needed to trigger the race.\nAC:L - The race is between attacker-driven sender workers and attacker-driven qdisc teardown/re-add operations, so both sides are controllable and repeatable.\nPR:L - Creating/deleting tc qdiscs requires CAP_NET_ADMIN, but tc/qdisc paths are reachable with namespace-scoped capabilities via user/network namespaces in plausible deployments.\nUI:N - No victim action is required once the attacker has local access and the needed namespace/network privileges.\nS:U - The impact is within the kernel and does not cross a distinct security authority such as a VM or device isolation boundary.\nC:H - The bug is a double-free/use-after-free of attacker-influenced skb memory, which can potentially be shaped into kernel heap disclosure primitives.\nI:H - The double-free/use-after-free corrupts kernel heap state and is plausibly exploitable for arbitrary write or control-flow corruption.\nA:H - KASAN reports confirm crashes in skb freeing, and repeated triggering can panic or otherwise take down the kernel." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "include/net/sch_generic.h", "net/sched/sch_generic.c", "net/sched/sch_teql.c" ], "versions": [ { "version": "96009c7d500efdd5534e83b2e3eb2c58d4b137ae", "lessThan": "4e8ebc4c18ea8213d28e6cb867d18fcc67daca21", "status": "affected", "versionType": "git" }, { "version": "96009c7d500efdd5534e83b2e3eb2c58d4b137ae", "lessThan": "21c89a0a8de7eadad8d385645a95b3233f23130e", "status": "affected", "versionType": "git" }, { "version": "96009c7d500efdd5534e83b2e3eb2c58d4b137ae", "lessThan": "afbc79a7770b230a9f24bd39271209d6b3682c5f", "status": "affected", "versionType": "git" }, { "version": "96009c7d500efdd5534e83b2e3eb2c58d4b137ae", "lessThan": "e9c66d3e7d8557b3308e55c613aa07254fe97611", "status": "affected", "versionType": "git" }, { "version": "96009c7d500efdd5534e83b2e3eb2c58d4b137ae", "lessThan": "4a233447b941db451ea5f5a0942cffd0f7f7eaae", "status": "affected", "versionType": "git" }, { "version": "96009c7d500efdd5534e83b2e3eb2c58d4b137ae", "lessThan": "66360460cab63c248ca5b1070a01c0c29133b960", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "include/net/sch_generic.h", "net/sched/sch_generic.c", "net/sched/sch_teql.c" ], "versions": [ { "version": "4.18", "status": "affected" }, { "version": "0", "lessThan": "4.18", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.167", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.130", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.78", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.20", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.19.10", "lessThanOrEqual": "6.19.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0", "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": "4.18", "versionEndExcluding": "6.1.167" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.18", "versionEndExcluding": "6.6.130" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.18", "versionEndExcluding": "6.12.78" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.18", "versionEndExcluding": "6.18.20" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.18", "versionEndExcluding": "6.19.10" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.18", "versionEndExcluding": "7.0" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/4e8ebc4c18ea8213d28e6cb867d18fcc67daca21" }, { "url": "https://git.kernel.org/stable/c/21c89a0a8de7eadad8d385645a95b3233f23130e" }, { "url": "https://git.kernel.org/stable/c/afbc79a7770b230a9f24bd39271209d6b3682c5f" }, { "url": "https://git.kernel.org/stable/c/e9c66d3e7d8557b3308e55c613aa07254fe97611" }, { "url": "https://git.kernel.org/stable/c/4a233447b941db451ea5f5a0942cffd0f7f7eaae" }, { "url": "https://git.kernel.org/stable/c/66360460cab63c248ca5b1070a01c0c29133b960" } ], "title": "net/sched: teql: Fix double-free in teql_master_xmit", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "x_adpType": "supplier", "providerMetadata": { "orgId": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e", "shortName": "siemens-SADP", "dateUpdated": "2026-07-14T12:47:06.095Z" }, "affected": [ { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.5", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.6", "lessThan": "*", "versionType": "custom" } ], "defaultStatus": "unknown" }, { "vendor": "Siemens", "product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP", "versions": [ { "status": "affected", "version": "V3.1.5", "lessThan": "*", 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