{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-68476","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-07-30T09:28:09.396Z","datePublished":"2026-08-15T05:51:32.170Z","dateUpdated":"2026-09-02T12:49:42.932Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-09-02T12:49:42.932Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nipvs: reload ip header after head reallocation\n\n__ip_vs_get_out_rt() calls skb_ensure_writable() which may\nreallocate skb->head."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":9.8,"baseSeverity":"CRITICAL"},"scenarios":[{"lang":"en","value":"AV:N - The flaw is in ip_vs_bypass_xmit() on the IPVS netfilter receive path (NF_INET_LOCAL_IN/FORWARD); remote IPv4 packets to a configured virtual-server VIP reach ip_vs_in_hook() and ip_vs_leave() without local syscalls or ioctl.\nAC:L - Once cache_bypass is enabled on a fwmark IPVS service with no backend, an attacker can repeatedly send traffic to the VIP; cloned skbs (common with bridging, mirroring, or shared receive buffers) make skb_ensure_writable() reallocate skb->head deterministically.\nPR:N - Exploitation requires only sending IP packets to the load balancer VIP; IPVS/cache_bypass configuration is an operator prerequisite on the target, not a Linux capability the remote attacker must hold.\nUI:N - No victim interaction is required; kernel processing of attacker-crafted network packets on the IPVS bypass transmit path alone triggers the stale header pointer use after skb head reallocation.\nS:U - Impact is kernel heap corruption and load-balancer compromise within the host kernel security domain; it does not cross VM, container, or IOMMU boundaries to another security authority.\nC:H - After pskb_expand_head() frees the old skb->head, ip_send_check() uses the stale iph pointer and ip_fast_csum() reads attacker-influenced bytes from freed kmalloc memory, a classic use-after-free information disclosure primitive.\nI:H - ip_send_check() writes through the stale iph pointer (zeroing and updating the checksum field) into freed/reallocated slab memory, enabling heap corruption and potential arbitrary kernel write or control-flow hijack primitives.\nA:H - Writing and reading through a stale IP header pointer after skb head reallocation can corrupt adjacent kernel heap objects or dereference freed memory, causing kernel oops, panic, or hang and repeatable 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/netfilter/ipvs/ip_vs_xmit.c"],"versions":[{"version":"8d8e20e2d7bba8c50e64e0eca1cb83956f468e49","lessThan":"4f2d1151421520d7ae16ca8d367d0ca09f5dfbd7","status":"affected","versionType":"git"},{"version":"8d8e20e2d7bba8c50e64e0eca1cb83956f468e49","lessThan":"657118cad620172dfd8f6ed5717fd75c0d1f7a5a","status":"affected","versionType":"git"},{"version":"8d8e20e2d7bba8c50e64e0eca1cb83956f468e49","lessThan":"a10f5080afbed242640f2984328de25f84557da1","status":"affected","versionType":"git"},{"version":"8d8e20e2d7bba8c50e64e0eca1cb83956f468e49","lessThan":"ac6ac3d35bfc0ade9d17d354c84e503a946ebdab","status":"affected","versionType":"git"},{"version":"8d8e20e2d7bba8c50e64e0eca1cb83956f468e49","lessThan":"e51687fc56c2e39ea6e9532925f1aabd4d529f61","status":"affected","versionType":"git"},{"version":"8d8e20e2d7bba8c50e64e0eca1cb83956f468e49","lessThan":"3fb7edd2018bb1ad0a68157383d9b9dac33dd645","status":"affected","versionType":"git"},{"version":"8d8e20e2d7bba8c50e64e0eca1cb83956f468e49","lessThan":"ad1e14710b360bda087ebf9fb82460eb5ef775de","status":"affected","versionType":"git"},{"version":"8d8e20e2d7bba8c50e64e0eca1cb83956f468e49","lessThan":"a2f57827bf7c695b8c72dc4511cae8e86582369d","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/netfilter/ipvs/ip_vs_xmit.c"],"versions":[{"version":"4.10","status":"affected"},{"version":"0","lessThan":"4.10","status":"unaffected","versionType":"semver"},{"version":"5.10.269","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.220","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.187","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.145","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.97","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.40","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.1.5","lessThanOrEqual":"7.1.*","status":"unaffected","versionType":"semver"},{"version":"7.2","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":"4.10","versionEndExcluding":"5.10.269"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.10","versionEndExcluding":"5.15.220"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.10","versionEndExcluding":"6.1.187"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.10","versionEndExcluding":"6.6.145"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.10","versionEndExcluding":"6.12.97"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.10","versionEndExcluding":"6.18.40"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.10","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.10","versionEndExcluding":"7.2"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/4f2d1151421520d7ae16ca8d367d0ca09f5dfbd7"},{"url":"https://git.kernel.org/stable/c/657118cad620172dfd8f6ed5717fd75c0d1f7a5a"},{"url":"https://git.kernel.org/stable/c/a10f5080afbed242640f2984328de25f84557da1"},{"url":"https://git.kernel.org/stable/c/ac6ac3d35bfc0ade9d17d354c84e503a946ebdab"},{"url":"https://git.kernel.org/stable/c/e51687fc56c2e39ea6e9532925f1aabd4d529f61"},{"url":"https://git.kernel.org/stable/c/3fb7edd2018bb1ad0a68157383d9b9dac33dd645"},{"url":"https://git.kernel.org/stable/c/ad1e14710b360bda087ebf9fb82460eb5ef775de"},{"url":"https://git.kernel.org/stable/c/a2f57827bf7c695b8c72dc4511cae8e86582369d"}],"title":"ipvs: reload ip header after head reallocation","x_generator":{"engine":"bippy-1.2.0"}}}}