{"id":"CVE-2026-93105","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nesp: do not unref managed frag pages in esp_ssg_unref()\n\nesp_ssg_unref() releases the page references held on the source\nscatterlist after the AEAD operation completes.…","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nesp: do not unref managed frag pages in esp_ssg_unref()\n\nesp_ssg_unref() releases the page references held on the source\nscatterlist after the AEAD operation completes.…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","vendor":"Linux","product":"Linux","affected":["Linux >= cac2661c53f35cbe651bef9b07026a5a05ab8ce0 < 26b6b14c7a0368e317a1e9fb5144ebe6f8d495cf","Linux >= cac2661c53f35cbe651bef9b07026a5a05ab8ce0 < 21697720ff43b8dfa25b8e8d9ca7f56f4597fc80","Linux 4.11"],"published":"2026-09-17","updated":"2026-09-18","sourceUpdated":"2026-09-18T18:18:20.667","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-93105","references":[{"url":"https://git.kernel.org/stable/c/21697720ff43b8dfa25b8e8d9ca7f56f4597fc80","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/26b6b14c7a0368e317a1e9fb5144ebe6f8d495cf","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"}],"tags":["nvd","cve.org"],"epss":0.00165,"epssPercentile":0.05024,"ingestedAt":"2026-09-17T16:21:47.756Z","slug":"CVE-2026-93105","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nesp: do not unref managed frag pages in esp_ssg_unref()\n\nesp_ssg_unref() releases the page references held on the source\nscatterlist after the AEAD operation completes.  It calls\nskb_page_unref() on every frag page for an out-of-place transform\n(req->src != req->dst), and in the error path of esp_output_tail()\n(already_unref == true) on the request's own scatterlist.\n\nThis is wrong when the skb carries managed frags\n(SKBFL_MANAGED_FRAG_REFS).  Managed frags are owned by a zerocopy ubuf\nand the skb does not hold a per-frag page reference; io_uring SEND_ZC\nwith a registered buffer attaches the bvec pages this way via\nio_sg_from_iter().  The rest of the stack honours this invariant:\nskb_release_data() skips the per-frag unref when SKBFL_MANAGED_FRAG_REFS\nis set, and skb_zcopy_managed() is the guard used at the other unref\nsites.\n\nesp_ssg_unref() is missing that guard, so for a managed-frag skb it\ndrops a page reference the skb never acquired.  This can underflow the\npage reference count and free a page that is still in use.\n\nGuard the function with skb_zcopy_managed() so both unref paths are\nskipped for managed-frag skbs, matching skb_release_data().\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":207371,"id":"CVE-2026-93105","ts":1789757341541,"field":"cvss","old":null,"new":"7.8"},{"seq":207370,"id":"CVE-2026-93105","ts":1789757341541,"field":"severity","old":"none","new":"high"}]}