{ "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-2024-36933", "sourceURL": "https://www.cve.org/CVERecord?id=CVE-2024-36933", "idYear": 2024, "status": "PUBLISHED", "publishedAt": "2024-05-30T15:29:23.764Z", "updatedAt": "2026-08-05T11:32:09.348Z", "importedAt": "2026-10-24T01:57:11.582Z", "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": "nsh: Restore skb->{protocol,data,mac_header} for outer header in nsh_gso_segment().", "summary": "In the Linux kernel, the following vulnerability has been resolved:\n\nnsh: Restore skb->{protocol,data,mac_header} for outer header in nsh_gso_segment().\n\nsyzbot triggered various splats (see [0] and links) by a crafted GSO\npacket of VIRTIO_NET_HDR_GSO_UDP layering the following protocols:\n\n ETH_P_8021AD + ETH_P_NSH + ETH_P_IPV6 + IPPROTO_UDP\n\nNSH can encapsulate IPv4, IPv6, Ethernet, NSH, and MPLS. As the inner\nprotocol can be Ethernet, NSH GSO handler, nsh_gso_segment(), calls\nskb_mac_gso_segment() to invoke inner protocol GSO handlers.\n\nnsh_gso_segment() does the following for the original skb before\ncalling skb_mac_gso_segment()\n\n 1. reset skb->network_header\n 2. save the original skb->{mac_heaeder,mac_len} in a local variable\n 3. pull the NSH header\n 4. resets skb->mac_header\n 5. set up skb->mac_len and skb->protocol for the inner protocol.\n\nand does the following for the segmented skb\n\n 6. set ntohs(ETH_P_NSH) to skb->protocol\n 7. push the NSH header\n 8. restore skb->mac_header\n 9. set skb->mac_header + mac_len to skb->network_header\n 10. restore skb->mac_len\n\nThere are two problems in 6-7 and 8-9.\n\n (a)\n After 6 & 7, skb->data points to the NSH header, so the outer header\n (ETH_P_8021AD in this case) is stripped when skb is sent out of netdev.\n\n Also, if NSH is encapsulated by NSH + Ethernet (so NSH-Ethernet-NSH),\n skb_pull() in the first nsh_gso_segment() will make skb->data point\n to the middle of the outer NSH or Ethernet header because the Ethernet\n header is not pulled by the second nsh_gso_segment().\n\n (b)\n While restoring skb->{mac_header,network_header} in 8 & 9,\n nsh_gso_segment() does not assume that the data in the linear\n buffer is shifted.\n\n However, udp6_ufo_fragment() could shift the data and change\n skb->mac_header accordingly as demonstrated by syzbot.\n\n If this happens, even the restored skb->mac_header points to\n the middle of the outer header.\n\nIt seems nsh_gso_segment() has never worked with outer headers so far.\n\nAt the end of nsh_gso_segment(), the outer header must be restored for\nthe segmented skb, instead of the NSH header.\n\nTo do that, let's calculate the outer header position relatively from\nthe inner header and set skb->{data,mac_header,protocol} properly.\n\n[0]:\nBUG: KMSAN: uninit-value in ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:524 [inline]\nBUG: KMSAN: uninit-value in ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:602 [inline]\nBUG: KMSAN: uninit-value in ipvlan_queue_xmit+0xf44/0x16b0 drivers/net/ipvlan/ipvlan_core.c:668\n ipvlan_process_outbound drivers/net/ipvlan/ipvlan_core.c:524 [inline]\n ipvlan_xmit_mode_l3 drivers/net/ipvlan/ipvlan_core.c:602 [inline]\n ipvlan_queue_xmit+0xf44/0x16b0 drivers/net/ipvlan/ipvlan_core.c:668\n ipvlan_start_xmit+0x5c/0x1a0 drivers/net/ipvlan/ipvlan_main.c:222\n __netdev_start_xmit include/linux/netdevice.h:4989 [inline]\n netdev_start_xmit include/linux/netdevice.h:5003 [inline]\n xmit_one net/core/dev.c:3547 [inline]\n dev_hard_start_xmit+0x244/0xa10 net/core/dev.c:3563\n __dev_queue_xmit+0x33ed/0x51c0 net/core/dev.c:4351\n dev_queue_xmit include/linux/netdevice.h:3171 [inline]\n packet_xmit+0x9c/0x6b0 net/packet/af_packet.c:276\n packet_snd net/packet/af_packet.c:3081 [inline]\n packet_sendmsg+0x8aef/0x9f10 net/packet/af_packet.c:3113\n sock_sendmsg_nosec net/socket.c:730 [inline]\n __sock_sendmsg net/socket.c:745 [inline]\n __sys_sendto+0x735/0xa10 net/socket.c:2191\n __do_sys_sendto net/socket.c:2203 [inline]\n __se_sys_sendto net/socket.c:2199 [inline]\n __x64_sys_sendto+0x125/0x1c0 net/socket.c:2199\n do_syscall_x64 arch/x86/entry/common.c:52 [inline]\n do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83\n entry_SYSCALL_64_after_hwframe+0x63/0x6b\n\nUninit was created at:\n slab_post_alloc_hook mm/slub.c:3819 [inline]\n slab_alloc_node mm/slub.c:3860 [inline]\n __do_kmalloc_node mm/slub.c:3980 [inline]\n __kmalloc_node_track_caller+0x705/0x1000 mm/slub.c:4001\n kmalloc_reserve+0x249/0x4a0 net/core/skbuff.c:582\n __\n---truncated---", "affected": [ { "vendor": "Linux", "product": "Linux", "defaultStatus": "unaffected", "versions": [ { "version": "c411ed854584a71b0e86ac3019b60e4789d88086", "status": "affected", "versionType": "git", "lessThan": "a7c2c3c1caabcb4a3d6c47284c397507aaf54fe9" }, { "version": "c411ed854584a71b0e86ac3019b60e4789d88086", "status": "affected", "versionType": "git", "lessThan": "46134031c20fd313d03b90169d64b2e05ca6b65c" }, { "version": "c411ed854584a71b0e86ac3019b60e4789d88086", "status": "affected", "versionType": "git", "lessThan": "bbccf0caef2fa917d6d0692385a06ce3c262a216" }, { "version": "c411ed854584a71b0e86ac3019b60e4789d88086", "status": "affected", "versionType": "git", "lessThan": "5a4603fbc285752d19e4b415466db18ef3617e4a" }, { "version": "c411ed854584a71b0e86ac3019b60e4789d88086", "status": "affected", "versionType": "git", "lessThan": "37ed6f244ec5bda2e90b085084e322ea55d0aaa2" }, { "version": "c411ed854584a71b0e86ac3019b60e4789d88086", "status": "affected", "versionType": "git", "lessThan": "696d18bb59727a2e0526c0802a812620be1c9340" }, { "version": "c411ed854584a71b0e86ac3019b60e4789d88086", "status": "affected", "versionType": "git", "lessThan": "29a07f2ee4d273760c2acbfc756e29eccd82470a" }, { "version": "c411ed854584a71b0e86ac3019b60e4789d88086", "status": "affected", "versionType": "git", "lessThan": "4b911a9690d72641879ea6d13cce1de31d346d79" } ] }, { "vendor": "Linux", "product": "Linux", "defaultStatus": "affected", "versions": [ { "version": "4.14", "status": "affected" }, { "version": "0", "status": "unaffected", "versionType": "semver", "lessThan": "4.14" }, { "version": "4.19.314", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "4.19.*" }, { "version": "5.4.276", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.4.*" }, { "version": "5.10.217", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.10.*" }, { "version": "5.15.159", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "5.15.*" }, { "version": "6.1.91", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.1.*" }, { "version": "6.6.31", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.6.*" }, { "version": "6.8.10", "status": "unaffected", "versionType": "semver", "lessThanOrEqual": "6.8.*" }, { "version": "6.9", "status": "unaffected", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*" } ] } ] } } }