The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - io_uring/zcrx: fix user_ref race between scrub and refill paths The io_zcrx_put_niov_uref() function uses     a non-atomic check-then-decrement pattern (atomic_read followed by separate atomic_dec) to manipulate     user_refs. This is serialized against other callers by rq_lock, but io_zcrx_scrub() modifies the same     counter with atomic_xchg() WITHOUT holding rq_lock. On SMP systems, the following race exists: CPU0     (refill, holds rq_lock) CPU1 (scrub, no rq_lock) put_niov_uref: atomic_read(uref) - 1 // window opens     atomic_xchg(uref, 0) - 1 return_niov_freelist(niov) [PUSH #1] // window closes atomic_dec(uref) - wraps to
    -1 returns true return_niov(niov) return_niov_freelist(niov) [PUSH #2: DOUBLE-FREE] The same niov is     pushed to the freelist twice, causing free_count to exceed nr_iovs. Subsequent freelist pushes then     perform an out-of-bounds write (a u32 value) past the kvmalloc'd freelist array into the adjacent slab     object. Fix this by replacing the non-atomic read-then-dec in io_zcrx_put_niov_uref() with an     atomic_try_cmpxchg loop that atomically tests and decrements user_refs. This makes the operation safe     against concurrent atomic_xchg from scrub without requiring scrub to acquire rq_lock. [pavel: removed a     warning and a comment] (CVE-2026-43121)

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Linux Distros Unpatched Vulnerability : CVE-2026-43121

medium Nessus Plugin ID 313159

Version 1.7

Version 1.5

Version 1.3

Version 1.1

Version 1.7 May 29, 2026, 5:27 PM CVSS metrics ("CVSSv2 score" set to 4.4. "CVSSv2 vector" set to "CVSS2#AV:L/AC:H/Au:S/C:N/I:N/A:C". "CVSSv2 vector" set to "CVSS2#AV:L/AC:M/Au:N/C:P/I:P/A:P") CVSSv2 severity (based on CVE-2026-43121, severity decreased from "Medium" to "Low". based on CVE-2026-43121, severity increased from "Low" to "Medium") Detection (updated detection logic) Plugin metadata Plugin Feed: 202605291727
Version 1.5 May 25, 2026, 10:30 PM Detection (updated detection logic) Plugin metadata Plugin Feed: 202605252230
Version 1.3 May 14, 2026, 3:47 AM CVSS metrics ("CVSSv3 score" set to 4.7. "CVSSv3 vector" set to "CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H") Detection (updated detection logic) Plugin metadata Plugin Feed: 202605140347
Version 1.1 May 8, 2026, 1:55 AM New Plugin Feed: 202605080155