CVE-2026-64320
CVE CVE-2026-64320EUVD EUVD-2026-49032Published 2026-07-25T08:49:48.000ZLast changed 2026-08-05T12:40:57.000ZCVSS 9.1
What the advisory describes
In the Linux kernel, the following vulnerability has been resolved: nvmet: fix pre-auth out-of-bounds heap read in Discovery Get Log Page nvmet_execute_disc_get_log_page() validates only the dword alignment of the host-supplied Log Page Offset (lpo). The 64-bit offset is then added to a small kzalloc'd buffer that holds the discovery log page and the result is passed straight to nvmet_copy_to_sgl(), which memcpy()s data_len bytes out to the host with no source-side bound check: u64 offset = nvmet_get_log_page_offset(req->cmd); /* 64-bit host */ size_t data_len = nvmet_get_log_page_len(req->cmd); /* 32-bit host */ ... if (offset & 0x3) { ... } /* only check */ ... alloc_len = sizeof(*hdr) + entry_size * discovery_log_entries(req); buffer = kzalloc(alloc_len, GFP_KERNEL); ... status = nvmet_copy_to_sgl(req, 0, buffer + offset, data_len); The Discovery controller is unauthenticated -- nvmet_host_allowed() returns true unconditionally for the discovery subsystem -- so the call is reachable pre-authentication by any TCP/RDMA/FC peer that can reach the nvmet target. With a discovery log page of ~1 KiB, an attacker requesting up to 4 KiB starting at offset == alloc_len reads the next slab page out and gets its content returned over the fabric (an empirical run on a default nvmet-tcp loopback target leaked 81 canonical kernel pointers in one Get Log Page response). Pointing the offset at unmapped kernel memory faults the in-kernel memcpy and crashes (or panics, on panic_on_oops=1) the target host instead. The attacker-controlled source-side offset pattern "nvmet_copy_to_sgl(req, 0, buffer + ATTACKER_OFFSET, ...)" is unique to nvmet_execute_disc_get_log_page in the entire nvmet codebase: every other Get Log Page handler in admin-cmd.c either ignores lpo (and silently starts every response at offset 0) or tracks a local destination offset with a fixed source pointer. Validate the host-supplied offset against the log page size, cap the copy length to what is actually available, and zero-fill any remainder of the host transfer buffer. The zero-fill matches the existing short-response pattern in nvmet_execute_get_log_changed_ns() (admin-cmd.c) and prevents leaking transport SGL contents when the host asks for more bytes than the log page contains.
Source: EUVD (ENISA), in the words of the advisory.
Products the advisory names
These come from the advisory itself, not from any check we performed.
- Linux — Linux a07b4970f464f13640e28e16dad6cfa33647cc99 <a29b316b9bbfd269f323ab4ba9906a894025680f; a07b4970f464f13640e28e16dad6cfa33647cc99 <33b974eb626154ae9348f2bac7de84cb2a3d9dd4; patch: 7.2-rc1; patch: 7.1.4; patch: 6.12.96; a07b4970f464f13640e28e16dad6cfa33647cc99 <53cd102a7a56079b11b897835bd9b94c14e6322c; patch: 6.18.39; a07b4970f464f13640e28e16dad6cfa33647cc99 <56c021a0869260d04c4b65d1471936aaf9177114; patch: 0; 4.8
The versions shown are the advisory's own. Patchlage compares no version numbers and derives no judgement from them — which version is installed is something a person has to look up.
Carried in the product catalogue
An estate covering these products can be recorded in Patchlage. An advisory about them appears in the next morning's situation report.
- Linux — Linux
Does this concern one of your customers?
This page cannot answer that — it does not know your estate. Whoever has recorded their environments gets the answer the morning after publication, together with a paragraph they can forward to the customer unedited.
Try it for 28 daysPatchlage reports hits and suspected hits. About everything else this system says nothing — neither this page nor the situation report ever claims that an estate is safe.