{"id":"CVE-2026-99284","published":"2026-11-07T21:17:00.603","lastModified":"2026-11-10T19:22:31.810","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: skbuff: propagate shared-frag marker in skb_zerocopy()\n\nskb_zerocopy() moves frag descriptors from @from into @to and takes a\nreference on each frag, but it does not copy skb_shinfo(from)->flags into\nskb_shinfo(to)->flags.  A destination skb holding the same page-cache\nbacked frags as the source therefore reports skb_has_shared_frag() as\nfalse.\n\nThat breaks the invariant relied on by later in-place writers.  ESP input\nchecks skb_has_shared_frag() before deciding whether an uncloned\nnonlinear skb can skip skb_cow_data(); with the marker lost, an skb that\nskb_zerocopy() built for nfnetlink_queue or for an openvswitch upcall is\ndecrypted in place, letting an unprivileged user write into the page\ncache of a root-owned read-only file.\n\nPropagate SKBFL_SHARED_FRAG when frag descriptors are copied, as done for\nthe other frag-transfer helpers.","cvssScore":null,"cvssSeverity":null,"cvssVector":null,"cwes":[],"vendors":[],"products":[],"references":[{"url":"https://git.kernel.org/stable/c/1a9c180cd8435917b7516edfb1c9148032c28773","tags":[]},{"url":"https://git.kernel.org/stable/c/1c623e3cbf43f12dd4a72712079bfa247a9b8ba3","tags":[]},{"url":"https://git.kernel.org/stable/c/79dc34beb1fdb3da79753e51e15c68591a2561fe","tags":[]},{"url":"https://git.kernel.org/stable/c/d7d6ff98d5d1b400f02211f962ac32cc0020aeab","tags":[]},{"url":"https://git.kernel.org/stable/c/fe8477e23dd2ee6bce231d65f2586a333b211dc0","tags":[]}],"exploitRefs":[],"hasPoc":false,"ai":null}