{ "schemaVersion": 1, "attribution": [ { "source": "CISA Known Exploited Vulnerabilities", "url": "https://www.cisa.gov/known-exploited-vulnerabilities-catalog", "licence": "US government work" }, { "source": "GitHub Advisory Database", "url": "https://github.com/advisories", "licence": "CC BY 4.0" }, { "source": "Have I Been Pwned", "url": "https://haveibeenpwned.com/", "licence": "CC BY 4.0" }, { "source": "CVE Program (CVE records)", "url": "https://www.cve.org/Legal/TermsOfUse", "licence": "CVE Terms of Use", "notice": "Copyright © 1999-2026, The MITRE Corporation. CVE is a trademark and the CVE logo is a registered trademark of The MITRE Corporation.", "terms": "CVE Usage: MITRE hereby grants you a perpetual, worldwide, non-exclusive, no-charge, royalty-free, irrevocable copyright license to reproduce, prepare derivative works of, publicly display, publicly perform, sublicense, and distribute Common Vulnerabilities and Exposures (CVE™). Any copy you make for such purposes is authorized provided that you reproduce MITRE's copyright designation and this license in any such copy." }, { "source": "FIRST EPSS", "url": "https://www.first.org/epss/", "licence": "free to use; FIRST requests attribution" } ], "record": { "id": "CVE-2023-53821", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2023-53821", "idYear": 2023, "status": "PUBLISHED", "publishedAt": "2025-12-09T01:29:34.073Z", "updatedAt": "2026-05-11T19:52:11.135Z", "importedAt": "2026-10-24T01:57:03.413Z", "snapshot": { "id": "cve_2026-10-24_midnight_baseline", "at": "2026-10-24T00:00:00.000Z", "source": "https://github.com/CVEProject/cvelistV5/releases/tag/cve_2026-10-24_0100Z" }, "facts": { "title": "ip6_vti: fix slab-use-after-free in decode_session6", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nip6_vti: fix slab-use-after-free in decode_session6\n\nWhen ipv6_vti device is set to the qdisc of the sfb type, the cb field\nof the sent skb may be modified during enqueuing. Then,\nslab-use-after-free may occur when ipv6_vti device sends IPv6 packets.\n\nThe stack information is as follows:\nBUG: KASAN: slab-use-after-free in decode_session6+0x103f/0x1890\nRead of size 1 at addr ffff88802e08edc2 by task swapper/0/0\nCPU: 0 PID: 0 Comm: swapper/0 Not tainted 6.4.0-next-20230707-00001-g84e2cad7f979 #410\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014\nCall Trace:\n\ndump_stack_lvl+0xd9/0x150\nprint_address_description.constprop.0+0x2c/0x3c0\nkasan_report+0x11d/0x130\ndecode_session6+0x103f/0x1890\n__xfrm_decode_session+0x54/0xb0\nvti6_tnl_xmit+0x3e6/0x1ee0\ndev_hard_start_xmit+0x187/0x700\nsch_direct_xmit+0x1a3/0xc30\n__qdisc_run+0x510/0x17a0\n__dev_queue_xmit+0x2215/0x3b10\nneigh_connected_output+0x3c2/0x550\nip6_finish_output2+0x55a/0x1550\nip6_finish_output+0x6b9/0x1270\nip6_output+0x1f1/0x540\nndisc_send_skb+0xa63/0x1890\nndisc_send_rs+0x132/0x6f0\naddrconf_rs_timer+0x3f1/0x870\ncall_timer_fn+0x1a0/0x580\nexpire_timers+0x29b/0x4b0\nrun_timer_softirq+0x326/0x910\n__do_softirq+0x1d4/0x905\nirq_exit_rcu+0xb7/0x120\nsysvec_apic_timer_interrupt+0x97/0xc0\n\nAllocated by task 9176:\nkasan_save_stack+0x22/0x40\nkasan_set_track+0x25/0x30\n__kasan_slab_alloc+0x7f/0x90\nkmem_cache_alloc_node+0x1cd/0x410\nkmalloc_reserve+0x165/0x270\n__alloc_skb+0x129/0x330\nnetlink_sendmsg+0x9b1/0xe30\nsock_sendmsg+0xde/0x190\n____sys_sendmsg+0x739/0x920\n___sys_sendmsg+0x110/0x1b0\n__sys_sendmsg+0xf7/0x1c0\ndo_syscall_64+0x39/0xb0\nentry_SYSCALL_64_after_hwframe+0x63/0xcd\nFreed by task 9176:\nkasan_save_stack+0x22/0x40\nkasan_set_track+0x25/0x30\nkasan_save_free_info+0x2b/0x40\n____kasan_slab_free+0x160/0x1c0\nslab_free_freelist_hook+0x11b/0x220\nkmem_cache_free+0xf0/0x490\nskb_free_head+0x17f/0x1b0\nskb_release_data+0x59c/0x850\nconsume_skb+0xd2/0x170\nnetlink_unicast+0x54f/0x7f0\nnetlink_sendmsg+0x926/0xe30\nsock_sendmsg+0xde/0x190\n____sys_sendmsg+0x739/0x920\n___sys_sendmsg+0x110/0x1b0\n__sys_sendmsg+0xf7/0x1c0\ndo_syscall_64+0x39/0xb0\nentry_SYSCALL_64_after_hwframe+0x63/0xcd\nThe buggy address belongs to the object at ffff88802e08ed00\nwhich belongs to the cache skbuff_small_head of size 640\nThe buggy address is located 194 bytes inside of\nfreed 640-byte region [ffff88802e08ed00, ffff88802e08ef80)\n\nAs commit f855691975bb (\"xfrm6: Fix the nexthdr offset in\n_decode_session6.\") showed, xfrm_decode_session was originally intended\nonly for the receive path. IP6CB(skb)->nhoff is not set during\ntransmission. Therefore, set the cb field in the skb to 0 before\nsending packets.", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "f855691975bb06373a98711e4cfe2c224244b536", "status": "affected", "versionType": "git", "lessThan": "0f0ab8d52ee0062b28367dea23c29e254a26d7db" }, { "version": "f855691975bb06373a98711e4cfe2c224244b536", "status": "affected", "versionType": "git", "lessThan": "fa6c6c04f6c9b21b315023f487e5a07ae7fcf647" }, { "version": "f855691975bb06373a98711e4cfe2c224244b536", "status": "affected", "versionType": "git", "lessThan": "eb47e612e59c358c3968a92f90dd36c78c9a2106" }, { "version": "f855691975bb06373a98711e4cfe2c224244b536", "status": "affected", "versionType": "git", "lessThan": "ec23b25e5687dbd644c0f57bcb6af22dd5a6dd36" }, { "version": "f855691975bb06373a98711e4cfe2c224244b536", "status": "affected", "versionType": "git", "lessThan": "a1639a82ce14af76b6419778d343ccbff86ee626" }, { "version": "f855691975bb06373a98711e4cfe2c224244b536", "status": "affected", "versionType": "git", "lessThan": "55ad2309205cc00c585344374c7472420e1b2c12" }, { "version": "f855691975bb06373a98711e4cfe2c224244b536", "status": "affected", "versionType": "git", "lessThan": "c070688bfbe7759e61e697e421b2a331b0dd74bc" }, { "version": "f855691975bb06373a98711e4cfe2c224244b536", "status": "affected", "versionType": "git", "lessThan": "9fd41f1ba638938c9a1195d09bc6fa3be2712f25" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "3.19", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "3.19" }, { "version": "4.14.324", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "4.14.*" }, { "version": "4.19.293", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "4.19.*" }, { "version": "5.4.255", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.4.*" }, { "version": "5.10.192", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.128", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.47", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.4.12", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.4.*" }, { "version": "6.5", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }