{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-63911","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-07-19T07:54:57.020Z","datePublished":"2026-07-19T14:55:16.496Z","dateUpdated":"2026-08-05T12:37:05.089Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-05T12:37:05.089Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: iptfs: reset runtime state when cloning SAs\n\niptfs_clone_state() clones the IPTFS mode data with kmemdup(). This\ncopies runtime objects which must not be shared with the original SA,\nincluding the embedded sk_buff_head, hrtimers, spinlock, and in-flight\nreassembly/reorder state.\n\nIf xfrm_state_migrate() fails after clone_state() but before the later\ninit_state() call has reinitialized those fields, the cloned state can be\ndestroyed by xfrm_state_gc_task() with list and timer state copied from the\noriginal SA. With queued packets this lets the clone splice and free skbs\nowned by the original IPTFS queue, leading to use-after-free and\ndouble-free reports in iptfs_destroy_state() and skb release paths.\n\nReinitialize the clone's runtime state before publishing it through\nx->mode_data. Because clone_state() now publishes a destroyable mode_data\nobject before init_state(), take the mode callback module reference there.\nAvoid taking it again from __iptfs_init_state() for the same object."}],"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 reached only through local XFRM SA migration via netlink XFRM_MSG_MIGRATE or PF_KEY SADB_X_MIGRATE, not by processing remote network packets alone.\nAC:L - On systems with IPTFS and XFRM_MIGRATE enabled, an attacker who controls the migrate request can reliably queue skbs on the SA and force a post-clone migration failure to trigger the shared-queue teardown.\nPR:L - All XFRM migrate operations require CAP_NET_ADMIN on the target network namespace, which unprivileged users can obtain inside a user namespace via unshare.\nUI:N - Exploitation requires no victim interaction beyond the attacker’s own netlink/PF_KEY operations and traffic through an SA they control.\nS:U - Impact is kernel memory corruption and privilege escalation within the same kernel security authority, not a cross-VM or cross-IOMMU boundary escape.\nC:H - The bug is a use-after-free on sk_buff objects where the clone’s destroy path frees skbs still owned by the live original IPTFS queue, enabling arbitrary kernel memory read primitives.\nI:H - Shared queue/timer state corruption and skb double-free provide exploitable heap corruption that can be leveraged for arbitrary kernel writes or code execution.\nA:H - The vulnerability causes kernel oops/panic from UAF and double-free in skb release paths, and can be used for repeatable denial of service against the host."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/xfrm/xfrm_iptfs.c"],"versions":[{"version":"0e4fbf013fa566f274ce9b4ce698c75b1f998c52","lessThan":"9327252e04626d4bb02ca8c0c108fbe8eabf0c5a","status":"affected","versionType":"git"},{"version":"0e4fbf013fa566f274ce9b4ce698c75b1f998c52","lessThan":"dfb9f6cbfa9826655a49698cf90eb800fce2178e","status":"affected","versionType":"git"},{"version":"0e4fbf013fa566f274ce9b4ce698c75b1f998c52","lessThan":"7f83d174073234839aea176f265e517e0d50a1d2","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/xfrm/xfrm_iptfs.c"],"versions":[{"version":"6.14","status":"affected"},{"version":"0","lessThan":"6.14","status":"unaffected","versionType":"semver"},{"version":"6.18.35","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.0.12","lessThanOrEqual":"7.0.*","status":"unaffected","versionType":"semver"},{"version":"7.1","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":"6.14","versionEndExcluding":"6.18.35"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.14","versionEndExcluding":"7.0.12"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.14","versionEndExcluding":"7.1"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/9327252e04626d4bb02ca8c0c108fbe8eabf0c5a"},{"url":"https://git.kernel.org/stable/c/dfb9f6cbfa9826655a49698cf90eb800fce2178e"},{"url":"https://git.kernel.org/stable/c/7f83d174073234839aea176f265e517e0d50a1d2"}],"title":"xfrm: iptfs: reset runtime state when cloning SAs","x_generator":{"engine":"bippy-1.2.0"}}}}